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Sample records for atrial arrhythmia triggers

  1. Air Pollution and the Triggering of Cardiac Arrhythmias

    Science.gov (United States)

    Link, Mark S.; Dockery, Douglas W.

    2013-01-01

    Purpose of Review The last five years have witnessed an explosion in interest regarding cardiac arrhythmias and air pollution. The data have been strongest with respect to ventricular arrhythmias but there is accumulating evidence that air pollution is also associated with supraventricular arrhythmias. Recent Findings There is clear epidemiological evidence linking air pollution and cardiac mortality. Whether the cardiac mortality was from myocardial ischemia, congestive heart failure or arrhythmic, or all of these pathways is not clear from the epidemiological data. There is a large body of evidence that air pollution can modify autonomic tone. More recent data, utilizing patients with cardiac disease and implantable cardioverter defibrillators (ICDs) has clarified the association of air pollution and arrhythmias. Data is also accumulating that air pollution may be associated with atrial arrhythmias. Summary The incremental risk of air pollution in triggering arrhythmias or other acute cardiac events is greatest for those patients with underlying cardiac disease. Cardiovascular patients and those at high risk of cardiovascular disease should be educated about the risks for triggering of arrhythmias and other cardiac events by air pollution. These patients should monitor the local forecasted Air Quality Index and follow the recommendations to reduce exposures and limit activities. PMID:19881339

  2. Mechanism for Triggered Waves in Atrial Myocytes.

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    Shiferaw, Yohannes; Aistrup, Gary L; Wasserstrom, J Andrew

    2017-08-08

    Excitation-contraction coupling in atrial cells is mediated by calcium (Ca) signaling between L-type Ca channels and Ryanodine receptors that occurs mainly at the cell boundary. This unique architecture dictates essential aspects of Ca signaling under both normal and diseased conditions. In this study we apply laser scanning confocal microscopy, along with an experimentally based computational model, to understand the Ca cycling dynamics of an atrial cell subjected to rapid pacing. Our main finding is that when an atrial cell is paced under Ca overload conditions, Ca waves can then nucleate on the cell boundary and propagate to the cell interior. These propagating Ca waves are referred to as "triggered waves" because they are initiated by L-type Ca channel openings during the action potential. These excitations are distinct from spontaneous Ca waves originating from random fluctuations of Ryanodine receptor channels, and which occur after much longer waiting times. Furthermore, we argue that the onset of these triggered waves is a highly nonlinear function of the sarcoplasmic reticulum Ca load. This strong nonlinearity leads to aperiodic response of Ca at rapid pacing rates that is caused by the complex interplay between paced Ca release and triggered waves. We argue further that this feature of atrial cells leads to dynamic instabilities that may underlie atrial arrhythmias. These studies will serve as a starting point to explore the nonlinear dynamics of atrial cells and will yield insights into the trigger and maintenance of atrial fibrillation. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  3. Atrial Arrhythmias and Their Implications for Space Flight - Introduction

    Science.gov (United States)

    Polk, J. D.; Barr, Y. R.; Bauer, P.; Hamilton, D. R.; Kerstman, E.; Tarver, B.

    2010-01-01

    This panel will discuss the implications of atrial arrhythmias in astronauts from a variety of perspectives; including historical data, current practices, and future challenges for exploration class missions. The panelists will present case histories, outline the evolution of current NASA medical standards for atrial arrhythmias, discuss the use of predictive tools, and consider potential challenges for current and future missions.

  4. Increasing Prevalence of Atrial Fibrillation and Permanent Atrial Arrhythmias in Congenital Heart Disease.

    Science.gov (United States)

    Labombarda, Fabien; Hamilton, Robert; Shohoudi, Azadeh; Aboulhosn, Jamil; Broberg, Craig S; Chaix, Marie A; Cohen, Scott; Cook, Stephen; Dore, Annie; Fernandes, Susan M; Fournier, Anne; Kay, Joseph; Macle, Laurent; Mondésert, Blandine; Mongeon, François-Pierre; Opotowsky, Alexander R; Proietti, Anna; Rivard, Lena; Ting, Jennifer; Thibault, Bernard; Zaidi, Ali; Khairy, Paul

    2017-08-15

    Atrial arrhythmias are the most common complication encountered in the growing and aging population with congenital heart disease. This study sought to assess the types and patterns of atrial arrhythmias, associated factors, and age-related trends. A multicenter cohort study enrolled 482 patients with congenital heart disease and atrial arrhythmias, age 32.0 ± 18.0 years, 45.2% female, from 12 North American centers. Qualifying arrhythmias were classified by a blinded adjudicating committee. The most common presenting arrhythmia was intra-atrial re-entrant tachycardia (IART) (61.6%), followed by atrial fibrillation (28.8%), and focal atrial tachycardia (9.5%). The proportion of arrhythmias due to IART increased with congenital heart disease complexity from 47.2% to 62.1% to 67.0% in patients with simple, moderate, and complex defects, respectively (p = 0.0013). Atrial fibrillation increased with age to surpass IART as the most common arrhythmia in those ≥50 years of age (51.2% vs. 44.2%; p heart disease, with a predominantly paroxysmal pattern. However, atrial fibrillation increases in prevalence and atrial arrhythmias progressively become permanent as the population ages. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  5. Right Atrial Diverticulosis and Early-onset Arrhythmia: Rare Cause of Incessant Neonatal Arrhythmia.

    Science.gov (United States)

    Aggarwal, Neeraj; Joshi, Raja; Joshi, Reena K; Agarwal, Mridul

    2017-06-15

    Atrial flutter not responding to medications could be secondary to structural malformations of heart. A 5-year-old child with resistant arrhythmia, with onset in neonatal period. Multiple right atrial diverticuli were detected on CT angiography and cardiac catheterization. Patient reverted to sinus rhythm following surgical excision of diverticuli. In cases of intractable supraventricular tachycardia, structural anomalies of atrium should be suspected.

  6. Atrial Arrhythmias in Astronauts - Summary of a NASA Summit

    Science.gov (United States)

    Barr, Yael R.; Watkins, Sharmila D.; Polk, J. D.

    2010-01-01

    Background and Problem Definition: To evaluate NASA s current standards and practices related to atrial arrhythmias in astronauts, Space Medicine s Advanced Projects Section at the Johnson Space Center was tasked with organizing a summit to discuss the approach to atrial arrhythmias in the astronaut cohort. Since 1959, 11 cases of atrial fibrillation, atrial flutter, or supraventricular tachycardia have been recorded among active corps crewmembers. Most of the cases were paroxysmal, although a few were sustained. While most of the affected crewmembers were asymptomatic, those slated for long-duration space flight underwent radiofrequency ablation treatment to prevent further episodes of the arrhythmia. The summit was convened to solicit expert opinion on screening, diagnosis, and treatment options, to identify gaps in knowledge, and to propose relevant research initiatives. Summit Meeting Objectives: The Atrial Arrhythmia Summit brought together a panel of six cardiologists, including nationally and internationally renowned leaders in cardiac electrophysiology, exercise physiology, and space flight cardiovascular physiology. The primary objectives of the summit discussions were to evaluate cases of atrial arrhythmia in the astronaut population, to understand the factors that may predispose an individual to this condition, to understand NASA s current capabilities for screening, diagnosis, and treatment, to discuss the risks associated with treatment of crewmembers assigned to long-duration missions or extravehicular activities, and to discuss recommendations for prevention or management of future cases. Summary of Recommendations: The summit panel s recommendations were grouped into seven categories: Epidemiology, Screening, Standards and Selection, Treatment of Atrial Fibrillation Manifesting Preflight, Atrial Fibrillation during Flight, Prevention of Atrial Fibrillation, and Future Research

  7. Atrial and ventricular function in thalassemic patients with supraventricular arrhythmias

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    Vitantonio Di Bello

    2009-04-01

    Full Text Available The aims of this study were to evaluate through Color Doppler Myocardial Imaging (CDMI echocardiography if atrial or ventricular myocardial alterations could be detectable in patients with thalassemia major (THAL and if these alterations could be considered as predictive elements for supra-ventricular arrhythmic events. Twenty-three patients with THAL underwent clinical and electrocardiographic evaluation; patients were grouped in THAL1 (9 with supra-ventricular arrhythmias and THAL2 (14 without arrhythmias; 12 healthy subjects were considered as control group (C. We examined through conventional 2D Color Doppler echocardiography some morphological and functional parameters regarding left ventricular (LV systolic and diastolic function, and through CDMI the velocities at mitral annulus level, the regional LV and left atrial (LA strain and strain rate. All THAL patients had LV dimension (pless than 0.05, LA area (p less than 0.01 and E/Em ratio (pless than 0.001 to be significantly higher than controls. The mitral annulus longitudinal velocities were significantly lower in THAL1 than in THAL2 (pless than 0.001; the E/Em ratio was higher in THAL1 than THAL2 (pless than 0.001. The THAL1 showed a lower systolic strain rate of atrial wall than THAL2 and C (pless than 0.05. The multiple regression highlighted a significantly inverse correlation among E/Em and atrial strain (pless than 0.02. CDMI showed both THAL subgroups had subtle systolic and diastolic left ventricular myocardial alterations, which could represent the onset of developing “iron cardiomyopathy” and are related to supra-ventricular arrhythmia. Monitoring these parameters in the THAL patients could contribute to decisions about follow-up and therapy.

  8. Atrial overdriving is beneficial in patients with atrial arrhythmias: first results of the PROVE Study.

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    Funck, R C; Adamec, R; Lurje, L; Capucci, A; Ritter, P; Shekan, D; Slegers, L C; Tavernier, R; Ishikawa, T

    2000-11-01

    The AF Prevention by Overdriving (PROVE) trial is an ongoing prospective study of the effectiveness of atrial overdrive pacing combined with an Automatic Rest Rate function in the prevention of atrial arrhythmias. All patients who have received a Talent DR 213 pacemaker are eligible for enrollment into the study. After a 1-month monitoring period, the patients are divided into two groups. Group I includes patients with > or = 2 appropriate mode-switch (MS) episodes, or 1 MS episode of > or = 10 minutes, and/or > 300 atrial runs of > 5 beats/month. Group II includes all other patients. The number and duration of atrial arrhythmias are measured the pacemaker's Automatic Interpretation and Data Analysis software (AIDA). Patients' quality-of-life is measured by a validated functional status questionnaire. After having been grouped, the patients are randomly assigned, in a crossover design, to standard DDDR or overdrive pacing + Rest Rate, each programmed for a 3-month period. Preliminary results in 78 patients show a 34% reduction in the mean number of MS, and a mean 48% shortening of the overall duration of the episodes by overdrive pacing + Rest Rate, achieved by a mean 84% prevalence of atrial pacing. Overdrive pacing + Rest Rate was well tolerated and associated with a slight improvement in quality-of-life.

  9. Applying non-linear dynamics to atrial appendage flow data to understand and characterize atrial arrhythmia

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    Chandra, S.; Grimm, R.A. [Cleveland Clinic Foundation, Cleveland, Ohio 44195 (United States); Katz, R. [Naval Undersea Warfare Center, New London, Connecticut 06320 (United States); Thomas, J.D. [Cleveland Clinic Foundation, Cleveland, Ohio 44195 (United States)

    1996-06-01

    The aim of this study was to better understand and characterize left atrial appendage flow in atrial fibrillation. Atrial fibrillation and flutter are the most common cardiac arrhythmias affecting 15% of the older population. The pulsed Doppler velocity profile data was recorded from the left atrial appendage of patients using transesophageal echocardiography. The data was analyzed using Fourier analysis and nonlinear dynamical tools. Fourier analysis showed that appendage mechanical frequency ({ital f{sub f}}) for patients in sinus rhythm was always lower (around1 Hz) than that in atrial fibrillation (5-8 Hz). Among patients with atrial fibrillation spectral power below {ital f{sub f}} was significantly different suggesting variability within this group of patients. Results that suggested the presence of nonlinear dynamics were: a) the existence of two arbitrary peak frequencies {ital f{sub 1}, f{sub 2}}, and other peak frequencies as linear combinations thereof ({ital mf{sub 1}{+-}nf{sub 2}}), and b) the similarity between the spectrum of patient data and that obtained using the Lorenz equation. Nonlinear analysis tools, including Phase plots and differential radial plots, were also generated from the velocity data using a delay of 10. In the phase plots, some patients displayed a torus-like structure, while others had a more random-like pattern. In the differential radial plots, the first set of patients (with torus-like phase plots) showed fewer values crossing an arbitrary threshold of 10 than did the second set (8 vs. 27 in one typical example). The outcome of cardioversion was different for these two set of patients. Fourier analysis helped to: differentiate between sinus rhythm and atrial fibrillation, understand the characteristics of the wide range of atrial fibrillation patients, and provide hints that atrial fibrillation could be a nonlinear process. Nonlinear dynamical tools helped to further characterize and sub-classify atrial fibrillation.

  10. Transgenic insights linking Pitx2 and atrial arrhythmias

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    Diego eFranco

    2012-06-01

    Full Text Available Pitx2 is a homeobox transcription factor involved in left–right signaling during embryogenesis. Disruption of left–right signaling in mice within its core nodal/lefty cascade, results in impaired expression of the last effector of the left–right cascade, Pitx2, leading in many cases to absence or bilateral expression of Pitx2 in lateral plate mesoderm (LPM. Loss of Pitx2 expression in LPM results in severe cardiac malformations, including right cardiac isomerism. Pitx2 is firstly expressed asymmetrically in the left but not right LPM, before the cardiac crescent forms, and subsequently, as the heart develops, becomes confined to the left side of the linear heart tube. Expression of Pitx2 is remodeled during cardiac looping, becoming localized to the ventral portion of the developing ventricular chambers, while maintaining a distinct left-sided atrial expression. The importance of Pitx2 during cardiogenesis has been illustrated by the complex and robust cardiac defects observed on systemic deletion of Pitx2 in mice. Lack of Pitx2 expression leads to embryonic lethality at mid-term, and Pitx2-deficient embryos display isomeric expression profile resulting in Pitx2 expression within both first and second heart fields during cardiogenesis, hearts and incomplete closure of the body wall. However, whereas the pivotal role of Pitx2 during cardiogenesis is well sustained, its putative role in the foetal and adult heart is largely unexplored. Recent genome-wide association studies have identified several genetic variants highly associated with atrial fibrillation (AF. Among them are genetic variants located on chromosome 4q25 adjacent to PITX2. Since then several transgenic approaches have provided evidences of the role of the homeobox transcription factor PITX2 and atrial arrhythmias. Here, we review new insights into the cellular and molecular links between PITX2 and atrial fibrillation.

  11. Transgenic insights linking pitx2 and atrial arrhythmias.

    Science.gov (United States)

    Franco, Diego; Chinchilla, Ana; Aránega, Amelia E

    2012-01-01

    Pitx2 is a homeobox transcription factor involved in left-right signaling during embryogenesis. Disruption of left-right signaling in mice within its core nodal/lefty cascade, results in impaired expression of the last effector of the left-right cascade, Pitx2, leading in many cases to absence or bilateral expression of Pitx2 in lateral plate mesoderm (LPM). Loss of Pitx2 expression in LPM results in severe cardiac malformations, including right cardiac isomerism. Pitx2 is firstly expressed asymmetrically in the left but not right LPM, before the cardiac crescent forms, and subsequently, as the heart develops, becomes confined to the left side of the linear heart tube. Expression of Pitx2 is remodeled during cardiac looping, becoming localized to the ventral portion of the developing ventricular chambers, while maintaining a distinct left-sided atrial expression. The importance of Pitx2 during cardiogenesis has been illustrated by the complex and robust cardiac defects observed on systemic deletion of Pitx2 in mice. Lack of Pitx2 expression leads to embryonic lethality at mid-term, and Pitx2-deficient embryos display isomeric hearts with incomplete closure of the body wall. However, whereas the pivotal role of Pitx2 during cardiogenesis is well sustained, its putative role in the fetal and adult heart is largely unexplored. Recent genome-wide association studies have identified several genetic variants highly associated with atrial fibrillation (AF). Among them are genetic variants located on chromosome 4q25 adjacent to PITX2. Since then several transgenic approaches have provided evidences of the role of the homeobox transcription factor PITX2 and atrial arrhythmias. Here, we review new insights into the cellular and molecular links between PITX2 and AF.

  12. Atrial arrhythmia in ageing spontaneously hypertensive rats: unraveling the substrate in hypertension and ageing.

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    Dennis H Lau

    Full Text Available BACKGROUND: Both ageing and hypertension are known risk factors for atrial fibrillation (AF although the pathophysiological contribution or interaction of the individual factors remains poorly understood. Here we aim to delineate the arrhythmogenic atrial substrate in mature spontaneously hypertensive rats (SHR. METHODS: SHR were studied at 12 and 15 months of age (n = 8 per group together with equal numbers of age-matched normotensive Wistar-Kyoto control rats (WKY. Electrophysiologic study was performed on superfused isolated right and left atrial preparations using a custom built high-density multiple-electrode array to determine effective refractory periods (ERP, atrial conduction and atrial arrhythmia inducibility. Tissue specimens were harvested for structural analysis. RESULTS: COMPARED TO WKY CONTROLS, THE SHR DEMONSTRATED: Higher systolic blood pressure (p<0.0001, bi-atrial enlargement (p<0.05, bi-ventricular hypertrophy (p<0.05, lower atrial ERP (p = 0.008, increased atrial conduction heterogeneity (p = 0.001 and increased atrial interstitial fibrosis (p = 0.006 & CD68-positive macrophages infiltration (p<0.0001. These changes resulted in higher atrial arrhythmia inducibility (p = 0.01 and longer induced AF episodes (p = 0.02 in 15-month old SHR. Ageing contributed to incremental bi-atrial hypertrophy (p<0.01 and atrial conduction heterogeneity (p<0.01 without affecting atrial ERP, fibrosis and arrhythmia inducibility. The limited effect of ageing on the atrial substrate may be secondary to the reduction in CD68-positive macrophages. CONCLUSIONS: Significant atrial electrical and structural remodeling is evident in the ageing spontaneously hypertensive rat atria. Concomitant hypertension appears to play a greater pathophysiological role than ageing despite their compounding effect on the atrial substrate. Inflammation is pathophysiologically linked to the pro-fibrotic changes in the hypertensive atria.

  13. Pitx2 prevents susceptibility to atrial arrhythmias by inhibiting left-sided pacemaker specification.

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    Wang, Jun; Klysik, Elzbieta; Sood, Subeena; Johnson, Randy L; Wehrens, Xander H T; Martin, James F

    2010-05-25

    Atrial fibrillation (AF), the most prevalent sustained cardiac arrhythmia, often coexists with the related arrhythmia atrial flutter (AFL). Limitations in effectiveness and safety of current therapies make an understanding of the molecular mechanism underlying AF more urgent. Genome-wide association studies implicated a region of human chromosome 4q25 in familial AF and AFL, approximately 150 kb distal to the Pitx2 homeobox gene, a developmental left-right asymmetry (LRA) gene. To investigate the significance of the 4q25 variants, we used mouse models to investigate Pitx2 in atrial arrhythmogenesis directly. When challenged by programmed stimulation, Pitx2(null+/-) adult mice had atrial arrhythmias, including AFL and atrial tachycardia, indicating that Pitx2 haploinsufficiency predisposes to atrial arrhythmias. Microarray and in situ studies indicated that Pitx2 suppresses sinoatrial node (SAN)-specific gene expression, including Shox2, in the left atrium of embryos and young adults. In vivo ChIP and transfection experiments indicated that Pitx2 directly bound Shox2 in vivo, supporting the notion that Pitx2 directly inhibits the SAN-specific genetic program in left atrium. Our findings implicate Pitx2 and Pitx2-mediated LRA-signaling pathways in prevention of atrial arrhythmias.

  14. Aortic stiffness in lone atrial fibrillation: a novel risk factor for arrhythmia recurrence.

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    Dennis H Lau

    Full Text Available BACKGROUND: Recent community-based research has linked aortic stiffness to the development of atrial fibrillation. We posit that aortic stiffness contributes to adverse atrial remodeling leading to the persistence of atrial fibrillation following catheter ablation in lone atrial fibrillation patients, despite the absence of apparent structural heart disease. Here, we aim to evaluate aortic stiffness in lone atrial fibrillation patients and determine its association with arrhythmia recurrence following radio-frequency catheter ablation. METHODS: We studied 68 consecutive lone atrial fibrillation patients who underwent catheter ablation procedure for atrial fibrillation and 50 healthy age- and sex-matched community controls. We performed radial artery applanation tonometry to obtain central measures of aortic stiffness: pulse pressure, augmentation pressure and augmentation index. Following ablation, arrhythmia recurrence was monitored at months 3, 6, 9, 12 and 6 monthly thereafter. RESULTS: Compared to healthy controls, lone atrial fibrillation patients had significantly elevated peripheral pulse pressure, central pulse pressure, augmentation pressure and larger left atrial dimensions (all P<0.05. During a mean follow-up of 2.9±1.4 years, 38 of the 68 lone atrial fibrillation patients had atrial fibrillation recurrence after initial catheter ablation procedure. Neither blood pressure nor aortic stiffness indices differed between patients with and without atrial fibrillation recurrence. However, patients with highest levels (≥75(th percentile of peripheral pulse pressure, central pulse pressure and augmentation pressure had higher atrial fibrillation recurrence rates (all P<0.05. Only central aortic stiffness indices were associated with lower survival free from atrial fibrillation using Kaplan-Meier analysis. CONCLUSION: Aortic stiffness is an important risk factor in patients with lone atrial fibrillation and contributes to higher atrial

  15. Arrhythmias, elicited by catecholamines and serotonin, vanish in human chronic atrial fibrillation

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    Christ, Torsten; Rozmaritsa, Nadiia; Engel, Andreas; Berk, Emanuel; Knaut, Michael; Metzner, Katharina; Canteras, Manuel; Ravens, Ursula; Kaumann, Alberto

    2014-01-01

    Atrial fibrillation (AF) is the most common heart rhythm disorder. Transient postoperative AF can be elicited by high sympathetic nervous system activity. Catecholamines and serotonin cause arrhythmias in atrial trabeculae from patients with sinus rhythm (SR), but whether these arrhythmias occur in patients with chronic AF is unknown. We compared the incidence of arrhythmic contractions caused by norepinephrine, epinephrine, serotonin, and forskolin in atrial trabeculae from patients with SR and patients with AF. In the patients with AF, arrhythmias were markedly reduced for the agonists and abolished for forskolin, whereas maximum inotropic responses were markedly blunted only for serotonin. Serotonin and forskolin produced spontaneous diastolic Ca2+ releases in atrial myocytes from the patients with SR that were abolished or reduced in myocytes from the patients with AF. For matching L-type Ca2+-current (ICa,L) responses, serotonin required and produced ∼100-fold less cAMP/PKA at the Ca2+ channel domain compared with the catecholamines and forskolin. Norepinephrine-evoked ICa,L responses were decreased by inhibition of Ca2+/calmodulin-dependent kinase II (CaMKII) in myocytes from patients with SR, but not in those from patients with AF. Agonist-evoked phosphorylation by CaMKII at phospholamban (Thr-17), but not of ryanodine2 (Ser-2814), was reduced in trabeculae from patients with AF. The decreased CaMKII activity may contribute to the blunting of agonist-evoked arrhythmias in the atrial myocardium of patients with AF. PMID:25024212

  16. Atrial adaptive rate pacing in sick sinus syndrome: effects on exercise capacity and arrhythmias.

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    Haywood, G.A.; Katritsis, D; Ward, J; Leigh-Jones, M; Ward, D. E.; Camm, A. J.

    1993-01-01

    OBJECTIVE--To test the hypotheses that adaptive rate atrial (AAIR) pacing: significantly increases maximal exercise capacity, and results in significant suppression of supraventricular and ventricular arrhythmia compared with fixed rate atrial (AAI) pacing. DESIGN--Prospective, randomised, single blind, crossover study with maximal treadmill exercise testing and 24 hour ambulatory electrocardiographic monitoring in AAIR and AAI modes. SETTING--Regional pacing centre. PATIENTS--30 consecutive ...

  17. Cardiovascular exercise and burden of arrhythmia in patients with atrial fibrillation

    DEFF Research Database (Denmark)

    Skielboe, Ane Katrine; Bandholm, Thomas Quaade; Hakmann, Stine

    2017-01-01

    BACKGROUND: Physical activity at moderate-high intensity is recommended to prevent lifestyle diseases. Patients with atrial fibrillation are at risk of a sedentary lifestyle due to fear of exercise-induced episodes of atrial fibrillation. The burden of arrhythmia can be reduced by physical exercise...... intensity physical exercise was not superior to low intensity physical exercise in reducing burden of atrial fibrillation. HI exercise was well tolerated; no evidence of an increased risk was found for HI compared to LI exercise. Larger studies are required to further prove our findings. TRIAL REGISTRATION...

  18. Is Initiating NOACs for Atrial Arrhythmias Safe in Adults with Congenital Heart Disease?

    NARCIS (Netherlands)

    Yang, Hayang; Bouma, Berto J.; Mulder, Barbara J. M.; Heidendael, J. F.; Veen, G.; Konings, T. C.; Sieswerda, G. T. J.; Meijboom, F. J.; Post, M. C.; van Dijk, A.; Budts, W.; Morissens, M.; Ladouceur, M.; Tobler, D.; Schwerzmann, M.; Rutz, T.; Bouchardy, J.; Greutmann, M.; Scognamiglio, G.; Skoglund, K.; Christersson, C.; Gumbiene, L.; Laukyte, M.; Khairy, P.; Aboulhosn, J.; Veldtman, G.; Webb, G.; Broberg, C. S.; Opotowsky, A. R.; Shafer, K.; Tsai, S. F.; Moe, T.; Niwa, K.; Mizuno, A.

    2017-01-01

    In recent years, non-vitamin K antagonist (VKA) oral anticoagulants (NOACs) have been increasingly prescribed to adults with congenital heart disease (CHD) and atrial arrhythmias without good evidence for either safety or efficacy. To address this gap, we initiated an ongoing prospective global

  19. Prevalence of right atrial non-pulmonary vein triggers in atrial fibrillation patients treated with thyroid hormone replacement therapy.

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    Kim, Ki-Hun; Mohanty, Sanghamitra; Mohanty, Prasant; Trivedi, Chintan; Morris, Eli Hamilton; Santangeli, Pasquale; Bai, Rong; Al-Ahmad, Amin; Burkhardt, John David; Gallinghouse, Joseph G; Horton, Rodney; Sanchez, Javier E; Bailey, Shane; Hranitzky, Patrick M; Zagrodzky, Jason; Kim, Soo G; Di Biase, Luigi; Natale, Andrea

    2017-08-01

    Thyroid hormone (TH) is known to enhance arrhythmogenicity, and high-normal thyroid function is related with an increased recurrence of atrial fibrillation (AF) after catheter ablation. However, the impact of thyroid hormone replacement (THR) on AF ablation is not well known. This study evaluated 1163 consecutive paroxysmal AF patients [160 (14%) on THR and 1003 (86%) without THR] undergoing their first catheter ablation. A total of 146 patients on THR and 146 controls were generated by propensity matching, based on calculated risk factor scores, using a logistic model (age, sex, body mass index, and left atrium size). The presence of non-pulmonary vein (PV) triggers was disclosed by a high-dose isoproterenol challenge (up to 30 μg/min) after PV isolation. Clinical characteristics were not different between the groups. When compared to the control, non-PV triggers were significantly greater in the THR patients [112 (77%) vs. 47 (32%), P right atrium (95 vs. 56%, P sources of non-PV triggers were the interatrial septum (25 vs. 11%, P = 0.002), coronary sinus (70 vs. 52%, P = 0.01), left atrial appendage (47 vs. 34%, P = 0.03), crista terminalis/superior vena cava (11 vs. 8%, P = 0.43), and mitral valve annulus (7 vs. 5%, P = 0.45) (THR vs. control), respectively. After mean follow-up of 14.7 ± 5.2 months, success rate was lower in patients on THR therapy [94 (64.4%)] compared to patients not receiving THR therapy [110 (75.3%), log-rank test value = 0.04]. Right atrial non-PV triggers were more prevalent in AF patients treated with THR. Elimination of non-PV triggers provided better arrhythmia-free survival in the non-THR group.

  20. Differential atrial performance at rest and exercise in athletes: Potential trigger for developing atrial dysfunction?

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    Gabrielli, L; Bijnens, B H; Brambila, C; Duchateau, N; Marin, J; Sitges-Serra, I; Mont, L; Brugada, J; Sitges, M

    2016-12-01

    Highly trained athletes show an increased risk of atrial arrhythmias. Little is known about atrial volumes and function during exercise in this population. Our aim was to analyze atrial size and contractile function during exercise. Fifty endurance athletes with 11 ± 8 h of training per week and 30 sedentary control subjects were included. Echocardiography was performed at baseline and during exercise. Left (LA) and right atrial (RA) size and function were assessed by two-dimensional echocardiography. Peak negative strain (Sa) during atrial contraction and active atrial emptying volume (AEV) were measured. Athletes and control subjects showed a significant increment of deformation and AEV of both atria with exercise (P athletes, a subgroup with significant LA (n = 8)/RA (n = 15) dilatation (≥40 mL/m(2) ) showed a significantly lower increment in AEV with exercise (LA∆AEV: 1.4 ± 1.1 mL/m(2) vs 2.1 ± 0.9 mL/m(2) , P = 0.04; RA∆AEV: 0.9 ± 0.8 mL/m(2) vs 2.3 ± 1.1 mL/m(2) , P athletes (LA∆Sa: -3.2 ± 2.9% vs -9.5 ± 4.4%, P athletes compared to controls, but due to larger atrial volumes, they reached similar increases in atrial emptying volume. However, this overall lesser deformation increases from a subgroup with significant atrial dilatation showing impairment in atrial contractile reserve. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Triggered intracellular calcium waves in dog and human left atrial myocytes from normal and failing hearts.

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    Aistrup, Gary L; Arora, Rishi; Grubb, Søren; Yoo, Shin; Toren, Benjamin; Kumar, Manvinder; Kunamalla, Aaron; Marszalec, William; Motiwala, Tej; Tai, Shannon; Yamakawa, Sean; Yerrabolu, Satya; Alvarado, Francisco J; Valdivia, Hector H; Cordeiro, Jonathan M; Shiferaw, Yohannes; Wasserstrom, John Andrew

    2017-11-01

    Abnormal intracellular Ca2+ cycling contributes to triggered activity and arrhythmias in the heart. We investigated the properties and underlying mechanisms for systolic triggered Ca2+ waves in left atria from normal and failing dog hearts. Intracellular Ca2+ cycling was studied using confocal microscopy during rapid pacing of atrial myocytes (36 °C) isolated from normal and failing canine hearts (ventricular tachypacing model). In normal atrial myocytes (NAMs), Ca2+ waves developed during rapid pacing at rates ≥ 3.3 Hz and immediately disappeared upon cessation of pacing despite high sarcoplasmic reticulum (SR) load. In heart failure atrial myocytes (HFAMs), triggered Ca2+ waves (TCWs) developed at a higher incidence at slower rates. Because of their timing, TCW development relies upon action potential (AP)-evoked Ca2+ entry. The distribution of Ca2+ wave latencies indicated two populations of waves, with early events representing TCWs and late events representing conventional spontaneous Ca2+ waves. Latency analysis also demonstrated that TCWs arise after junctional Ca2+ release has occurred and spread to non-junctional (cell core) SR. TCWs also occurred in intact dog atrium and in myocytes from humans and pigs. β-adrenergic stimulation increased Ca2+ release and abolished TCWs in NAMs but was ineffective in HFAMs making this a potentially effective adaptive mechanism in normals but potentially arrhythmogenic in HF. Block of Ca-calmodulin kinase II also abolished TCWs, suggesting a role in TCW formation. Pharmacological manoeuvres that increased Ca2+ release suppressed TCWs as did interventions that decreased Ca2+ release but these also severely reduced excitation-contraction coupling. TCWs develop during the atrial AP and thus could affect AP duration, producing repolarization gradients and creating a substrate for reentry, particularly in HF where they develop at slower rates and a higher incidence. TCWs may represent a mechanism for the initiation

  2. Value of the Ratio of Occluder Versus Atrial Septal Length for Predicting Arrhythmia Occurrence after Transcatheter Closure in Children with Ostium Secundum Atrial Septal Defect

    Directory of Open Access Journals (Sweden)

    Mei Jin

    2015-01-01

    Full Text Available Background: Transcatheter occlusion has been applied to treat ostium secundum atrial septal defect (OS ASD since 1997. During the clinical practice, several postoperative complications including arrhythmia have been reported. This study aimed to evaluate the value of the ratio of atrial septal occluder (ASO versus atrial septal length (ASL for predicting arrhythmia occurrence after transcatheter closure in children with OS ASD. Methods: Six hundred and fifty-one children diagnosed with OS ASD underwent occlusion procedures after completing routine examinations. The onsets and types of arrhythmia both during and after the occlusion procedures were monitored. Treatments were given based on the individual types of arrhythmia. The binary logistic regression analysis and receiver-operating characteristic (ROC curve were used in the analysis of value of the ratio of ASO/ASL for predicting postoperative arrhythmia occurrence. Results: Transcather occlusions were conducted in 651 children, among whom 7 children had different types and degrees of arrhythmia, with an incidence of 1.1%. The types of arrhythmia included sinus bradycardia, atrial premature beats, bundle branch block, and different degrees of atrioventricular block. Normal electrocardiograph findings were resumed in these 7 patients following active therapies such as corticoids, nutrition, and surgeries. The binary logistic regression and ROC analysis suggested that the ratio of ASO/ASL exhibited an intermediate predictive value for predicting arrhythmia occurrence after occlusion procedures. A cut-off value of 0.576 in the ratio provided a sensitivity of 87.5% and a specificity of 76.2% with an area under the ROC curve of 0.791 (95% confidence intervals, 0.655-0.926; P < 0.05 in predicting arrhythmia occurrence after the closure procedures. Conclusions: The ratio of ASO/ASL might be a useful index for predicting arrhythmia occurrence after closure procedures in children with OS ASD.

  3. Atrial adaptive rate pacing in sick sinus syndrome: effects on exercise capacity and arrhythmias.

    Science.gov (United States)

    Haywood, G A; Katritsis, D; Ward, J; Leigh-Jones, M; Ward, D E; Camm, A J

    1993-02-01

    To test the hypotheses that adaptive rate atrial (AAIR) pacing: significantly increases maximal exercise capacity, and results in significant suppression of supraventricular and ventricular arrhythmia compared with fixed rate atrial (AAI) pacing. Prospective, randomised, single blind, crossover study with maximal treadmill exercise testing and 24 hour ambulatory electrocardiographic monitoring in AAIR and AAI modes. Regional pacing centre. 30 consecutive patients (mean SD age 65 (12) years) with sick sinus syndrome who required permanent pacing, without evidence of conduction disturbance on 12 lead electrocardiograms or 24 hour ambulatory electrocardiographic monitoring and without other cardiovascular or systemic disease. Activity sensing or minute ventilation driven systems (AAI/AAIR) were implanted alternately. The mean (SD) peak heart rate in AAI mode was 122(28)v 130(22) in AAIR mode (p AAIR mode (NS) in the chronotropically incompetent patients. There were no significant differences in the Borg scores at peak exercise in AAI v AAIR mode in either group. The frequency per hour of atrial and ventricular arrhythmias showed no significant differences between the two modes in either the group as a whole or in the subgroups with chronotropic incompetence. AAIR pacing confers little benefit in sick sinus syndrome compared with AAI pacing.

  4. Arrhythmias

    Directory of Open Access Journals (Sweden)

    Hanan Zaghla

    2013-07-01

    Conclusion: Our results rule out the electropathy hypothesis and underline autonomic neuropathy as the most possible mechanism of arrhythmias in hypoxaemic, non-respiratory failure, and COPD patients.

  5. Recurrence of arrhythmia following short-term oral AMIOdarone after CATheter ablation for atrial fibrillation

    DEFF Research Database (Denmark)

    Darkner, Stine; Chen, Xu; Hansen, Jim

    2014-01-01

    later recurrence. METHODS AND RESULTS: In a two-centre, randomized, double-blind, placebo-controlled study, we randomized a total of 212 patients undergoing AF ablation. Patients were stratified according to type of AF (paroxysmal/persistent) and history of previous AF ablation and randomly assigned...... to 8 weeks of oral amiodarone therapy or matched placebo following catheter ablation. Patients were followed for 6 months. Analyses were performed according to the intention-to-treat principle. Of 212 enrolled patients [median age 61 (inter-quartile range 54-66), 83% male, 50% paroxysmal, 29...... period. CONCLUSION: Short-term oral amiodarone treatment following ablation for paroxysmal or persistent AF did not significantly reduce recurrence of atrial tachyarrhythmias at the 6-month follow-up, but it more than halved atrial arrhythmia related hospitalization and cardioversion rates during...

  6. The Relationship between Left Atrial Volume and Ventricular Arrhythmias in the Patients with Dilated Cardiomyopathy

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    Abdullah Kaplan

    2014-03-01

    Full Text Available Background:: The present study aimed to investigate the relationship between Left Atrial Volume (LAV, a marker of diastolic dysfunction, and the frequency of malignant ventricular arrhythmia in the patients with left ventricular dysfunction and a previously implanted Implantable Cardioverter Defibrillator (ICD device. Methods:: This cross-sectional study was conducted on 32 patients with ischemic or idiopathic dilated cardiomyopathy, each having had an ICD device implanted at least 1 year beforehand. The ventricular arrhythmia episodes which were detected and stored by the device were retrieved and evaluated. In addition to routine echocardiographic measurements, all the patients had their LAV and LAV indexes calculated. After all, student’s t-test, Mann-Whitney U test, and Pearson correlation were used to analyze the data. Besides, P value < 0.05 was considered as statistically significant. Results:: This study was conducted on 4 female and 28 male patients with the mean age of 58.41 ± 9.97 years. Among the study patients, 21 had at least one previous myocardial infarction. In addition, 17 patients had experienced sustained VT or VF within the last year. No significant difference was found between the patients with and without malignant ventricular arrhythmias (sustained VT or VF regarding LAV (17 patients with arrhythmia (68 + 23.39 mL vs. 15 patients without arrhythmia (55.13 ± 20.41 mL; P = 0.100. However, the LAV index was significantly higher in the patients with arrhythmia compared to those without arrhythmia (39.27 ± 12.19 mL / m2 vs. 25.18 ± 7.45 mL / m2; P = 0.004. Both LAV (73.33 ± 17.64 mL and 57.52 ± 23.15 mL, respectively; P = 0.040 and LAV index (40.86 ± 8.47 mL / m2 and 28.20 ± 11.77 mL / m2, respectively; P = 0.010 were significantly greater in the patients with ICD shock therapy within the last year compared to the others. However, both groups were similar regarding Left Ventricular Volume (LVV, LVV index, and

  7. Multimodality Cardiac Imaging for the Assessment of Left Atrial Function and the Association With Atrial Arrhythmias

    DEFF Research Database (Denmark)

    Olsen, Flemming Javier; Bertelsen, Litten; de Knegt, Martina Chantal

    2016-01-01

    an inverse relationship between LA reservoir function and degree of LA fibrosis. This has sparked an increased interest into the application of advanced imaging modalities, including both speckle tracking echocardiography and tissue tracking by cardiac magnetic resonance imaging. Even though increasing......Several cardiac imaging modalities are able to visualize the left atrium (LA) and, therefore, allow for quantification of both structural and functional properties of this cardiac chamber. In echocardiography, only the maximal LA volume is included in the assessment of diastolic function...... atrial fibrillation, which will be a point of focus in this review. Pivotal cardiac magnetic resonance imaging studies have revealed high correlation between LA fibrosis and risk of atrial fibrillation recurrence after catheter ablation, and subsequent multimodality imaging studies have uncovered...

  8. Short runs of atrial arrhythmia and stroke risk: a European-wide online survey among stroke physicians and cardiologists.

    Science.gov (United States)

    Tran, R T; Rankin, A J; Abdul-Rahim, A H; Lip, G Y; Rankin, A C; Lees, K R

    2016-06-01

    A recording of = 30 seconds is required to diagnose paroxysmal atrial fibrillation when using ambulatory ECG monitoring. It is unclear if shorter runs are relevant with regards to stroke risk. Methods An online survey of cardiologists and stroke physicians was carried out to assess current management of patients with short runs of atrial arrhythmia within Europe. Results Respondents included 311 clinicians from 32 countries. To diagnose atrial fibrillation, 80% accepted a single 12-lead ECG and 36% accepted a single run of > 30 seconds on ambulatory monitoring. Stroke physicians were twice as likely to accept < 30 seconds of arrhythmia as being diagnostic of atrial fibrillation (OR 2.43, 95% CI 1.19-4.98). They were also more likely to advocate anticoagulation for hypothetical patients with lower risk; OR 1.9 (95% CI 1.0-3.5) for a patient with CHA2DS2-VASc = 2. Conclusion Short runs of atrial fibrillation create a dilemma for physicians across Europe. Stroke physicians and cardiologists differ in their diagnosis and management of these patients.

  9. The relationship between ECG signs of atrial infarction and the development of supraventricular arrhythmias in patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Nielsen, F E; Andersen, H H; Gram-Hansen, P

    1992-01-01

    ECGs obtained on arrival at the hospital from 277 patients with acute myocardial infarction were analyzed retrospectively for PR displacements, which were classified as major or minor criteria for atrial infarction and related to the later occurrence of supraventricular arrhythmia in the hospital....... Major criteria were (1) PR segment elevation greater than 0.5 mm in leads V5 and V6 with reciprocal PR segment depression in leads V1 and V2, (2) PR segment elevation greater than 0.5 mm in lead I with reciprocal PR segment depression in leads II and III, and (3) PR segment depression greater than 1...... arrhythmias, giving odds ratios of 9.9 and 3.7, respectively. Enzyme-estimated infarct size, the occurrence of heart failure, and mortality rates did not differ in patients with or without major criteria for atrial infarction. We conclude that the occurrence of PR segment displacements on the admission ECG...

  10. Remodeling of cardiac passive electrical properties and susceptibility to ventricular and atrial arrhythmias

    Directory of Open Access Journals (Sweden)

    Stefan eDhein

    2014-11-01

    Full Text Available Coordinated electrical activation of the heart is essential for the maintenance of a regular cardiac rhythm and effective contractions. Action potentials spread from one cell to the next via gap junction channels. Because of the elongated shape of cardiomyocytes, longitudinal resistivity is lower than transverse resistivity causing electrical anisotropy. Moreover, non-uniformity is created by clustering of gap junction channels at cell poles and by non-excitable structures such as collagenous strands, vessels or fibroblasts. Structural changes in cardiac disease often affect passive electrical properties by increasing non-uniformity and altering anisotropy. This disturbs normal electrical impulse propagation and is, consequently, a substrate for arrhythmia. However, to investigate how these structural changes lead to arrhythmias remains a challenge. One important mechanism, which may both cause and prevent arrhythmia, is the mismatch between current sources and sinks. Propagation of the electrical impulse requires a sufficient source of depolarizing current. In the case of a mismatch, the activated tissue (source is not able to deliver enough depolarizing current to trigger an action potential in the non-activated tissue (sink. This eventually leads to conduction block. It has been suggested that in this situation a balanced geometrical distribution of gap junctions and reduced gap junction conductance may allow successful propagation. In contrast, source-sink mismatch can prevent spontaneous arrhythmogenic activity in a small number of cells from spreading over the ventricle, especially if gap junction conductance is enhanced. Beside gap junctions, cell geometry and non-cellular structures strongly modulate arrhythmogenic mechanisms. The present review elucidates these and other implications of passive electrical properties for cardiac rhythm and arrhythmogenesis.

  11. CARDIAC ARRHYTHMIAS IN MEDICAL PRACTICE: CLINICAL CASE OF AMIODARONE-INDUCED THYROTOXICOSIS TYPE 2 AS A CAUSE OF RECURRENT ATRIAL FIBRILLATION

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    O. V. Gaisenok

    2010-01-01

    Full Text Available Atrial fibrillation is a common cardiac arrhythmia. Amiodarone is an effective drug used for atrial fibrillation treatment. Various side effects of this drug including amiodarone-induced thyrotoxicosis are discussed. A clinical case is presented to provide data for the differential diagnosis between types 1 and 2 of amiodarone-induced thyrotoxicosis and to define approaches to the treatment.

  12. Calsequestrin 2 deletion causes sinoatrial node dysfunction and atrial arrhythmias associated with altered sarcoplasmic reticulum calcium cycling and degenerative fibrosis within the mouse atrial pacemaker complex1

    Science.gov (United States)

    Glukhov, Alexey V.; Kalyanasundaram, Anuradha; Lou, Qing; Hage, Lori T.; Hansen, Brian J.; Belevych, Andriy E.; Mohler, Peter J.; Knollmann, Björn C.; Periasamy, Muthu; Györke, Sandor; Fedorov, Vadim V.

    2015-01-01

    Aims Loss-of-function mutations in Calsequestrin 2 (CASQ2) are associated with catecholaminergic polymorphic ventricular tachycardia (CPVT). CPVT patients also exhibit bradycardia and atrial arrhythmias for which the underlying mechanism remains unknown. We aimed to study the sinoatrial node (SAN) dysfunction due to loss of CASQ2. Methods and results In vivo electrocardiogram (ECG) monitoring, in vitro high-resolution optical mapping, confocal imaging of intracellular Ca2+ cycling, and 3D atrial immunohistology were performed in wild-type (WT) and Casq2 null (Casq2−/−) mice. Casq2−/− mice exhibited bradycardia, SAN conduction abnormalities, and beat-to-beat heart rate variability due to enhanced atrial ectopic activity both at baseline and with autonomic stimulation. Loss of CASQ2 increased fibrosis within the pacemaker complex, depressed primary SAN activity, and conduction, but enhanced atrial ectopic activity and atrial fibrillation (AF) associated with macro- and micro-reentry during autonomic stimulation. In SAN myocytes, CASQ2 deficiency induced perturbations in intracellular Ca2+ cycling, including abnormal Ca2+ release, periods of significantly elevated diastolic Ca2+ levels leading to pauses and unstable pacemaker rate. Importantly, Ca2+ cycling dysfunction occurred not only at the SAN cellular level but was also globally manifested as an increased delay between action potential (AP) and Ca2+ transient upstrokes throughout the atrial pacemaker complex. Conclusions Loss of CASQ2 causes abnormal sarcoplasmic reticulum Ca2+ release and selective interstitial fibrosis in the atrial pacemaker complex, which disrupt SAN pacemaking but enhance latent pacemaker activity, create conduction abnormalities and increase susceptibility to AF. These functional and extensive structural alterations could contribute to SAN dysfunction as well as AF in CPVT patients. PMID:24216388

  13. Atrial fibrillation ablation in Brazil: results of the registry of the Brazilian Society of Cardiac Arrhythmias.

    Science.gov (United States)

    Fenelon, Guilherme; Scanavacca, Maurício; Atié, Jacob; Zimerman, Leandro; Magalhães, Luiz Pereira de; Lorga Filho, Adalberto; Maia, Henrique; Martinelli Filho, Martino

    2007-11-01

    Aiming to define the profile of curative atrial fibrillation (AF) ablation in Brazil, the Brazilian Cardiac Arrhythmia Society [Sociedade Brasileira de Arritmias Cardíacas] (SOBRAC) created the Brazilian Registry of AF Ablation [Registro Brasileiro de Ablação da FA]. To describe the results of this registry. A questionnaire was sent to SOBRAC members asking about data on patients submitted to AF ablation between September 2005 and November, 2006. A total of 29 groups from 13 states completed the forms. Of these, 22 (76%) had performed AF ablations. Between 1998 and 2001, 7 groups (32%) initiated AF ablations and between 2002 and 2006, 15 groups began to perform them (68%). From 1998 to 2006, 2,374 patients were submitted to ablation, 755 (32%) of them during the registry period. Most (70%) were males and 89% presented with paroxysmal or persistent AF. Ancillary imaging methods (intracardiac echocardiography and electroanatomic mapping) were used by 9 groups (41%). During an average five-month follow-up period, total success was 82% and success without use of antiarrhythmic agents was 57%. Nevertheless, 35% of the patients required two or more procedures. There were 111 complications (14.7%) and 2 deaths (0.26%). Curative AF ablation has been increasing significantly in our country, with success rates comparable to international indexes, but often more than one procedure is necessary. Despite promising results, AF ablation still results in significant morbidity. Supplementary imaging methods have been used more and more in an effort to increase efficacy and safety of the procedure. These findings should be considered by public and private funding agencies.

  14. Assessment of Atrial Fibrillation and Ventricular Arrhythmia Risk after Bariatric Surgery by P Wave/QT Interval Dispersion.

    Science.gov (United States)

    Yılmaz, Mustafa; Altın, Cihan; Tekin, Abdullah; Erol, Tansel; Arer, İlker; Nursal, Tarık Zafer; Törer, Nurkan; Erol, Varlık; Müderrisoğlu, Haldun

    2017-09-13

    The association of obesity with atrial fibrillation (AF) and with ventricular arrhythmias is well documented. The aim of this study was to investigate whether weight reduction by a laparoscopic sleeve gastrectomy has any effect on P wave dispersion (PWD), a predictor of AF, and corrected QT interval dispersion (CQTD), a marker of ventricular arrhythmias, in obese individuals. In a prospective study, a total of 114 patients (79 females, 35 males) who underwent laparoscopic sleeve gastrectomy were examined. The patients were followed 1 year. PWD and CQTD values before and 3rd, 6th, and 12th months after the surgery were calculated and compared. There was a statistically significant decline in body mass index (BMI), PWD, and CQTD values among baseline, 3rd, 6th, and 12th months (p p p = 0.002), ΔPWD and Δleft atrial diameter (LAD) (r = 0.65, p p = 0.004), ΔCQTD and ΔLVEDD (r = 0.35, p p = 0.002). In multiple linear regression analysis, there was a statistically significant relationship between ΔPWD and ΔBMI (β = 0.713, p p = 0.016), ΔPWD and ΔLAD (β = 0.619, p p = 0.011), ΔCQTD and ΔLVEDD (β = 0.304, p p = 0.009). PWD and CQTD values of patients were shown to be attenuated after bariatric surgery. These results indirectly offer that there may be a reduction in risk of AF, ventricular arrhythmia, and sudden cardiac death after obesity surgery.

  15. A computational framework for testing arrhythmia marker sensitivities to model parameters in functionally calibrated populations of atrial cells

    Science.gov (United States)

    Vagos, Márcia R.; Arevalo, Hermenegild; de Oliveira, Bernardo Lino; Sundnes, Joakim; Maleckar, Mary M.

    2017-09-01

    Models of cardiac cell electrophysiology are complex non-linear systems which can be used to gain insight into mechanisms of cardiac dynamics in both healthy and pathological conditions. However, the complexity of cardiac models can make mechanistic insight difficult. Moreover, these are typically fitted to averaged experimental data which do not incorporate the variability in observations. Recently, building populations of models to incorporate inter- and intra-subject variability in simulations has been combined with sensitivity analysis (SA) to uncover novel ionic mechanisms and potentially clarify arrhythmogenic behaviors. We used the Koivumäki human atrial cell model to create two populations, representing normal Sinus Rhythm (nSR) and chronic Atrial Fibrillation (cAF), by varying 22 key model parameters. In each population, 14 biomarkers related to the action potential and dynamic restitution were extracted. Populations were calibrated based on distributions of biomarkers to obtain reasonable physiological behavior, and subjected to SA to quantify correlations between model parameters and pro-arrhythmia markers. The two populations showed distinct behaviors under steady state and dynamic pacing. The nSR population revealed greater variability, and more unstable dynamic restitution, as compared to the cAF population, suggesting that simulated cAF remodeling rendered cells more stable to parameter variation and rate adaptation. SA revealed that the biomarkers depended mainly on five ionic currents, with noted differences in sensitivities to these between nSR and cAF. Also, parameters could be selected to produce a model variant with no alternans and unaltered action potential morphology, highlighting that unstable dynamical behavior may be driven by specific cell parameter settings. These results ultimately suggest that arrhythmia maintenance in cAF may not be due to instability in cell membrane excitability, but rather due to tissue-level effects which

  16. Robotic navigation in catheter ablation for paroxysmal atrial fibrillation: midterm efficacy and predictors of postablation arrhythmia recurrences.

    Science.gov (United States)

    Hlivák, Peter; Mlčochová, Hanka; Peichl, Petr; Cihák, Robert; Wichterle, Dan; Kautzner, Josef

    2011-05-01

    Remote navigation systems represent a novel strategy for catheter ablation of atrial fibrillation (AF). The goal of this study is to describe a single-center experience with the electromechanical robotic system (Sensei, Hansen Medical) in treatment of patients with paroxysmal AF. Out of 200 patients who underwent robotically guided ablation for AF between 2007 and 2009 at our institute, 100 patients (29 women, age 56.5 ± 10 years) had paroxysmal AF refractory to antiarrhythmic drugs. Electroanatomic mapping using NavX system (St. Jude Medical) provided anatomical shell for subsequent circumferential ablation with robotic catheter (Artisan) loaded with a 3.5-mm, open-irrigation, cooled-tip ablation catheter. A mean of 69 radiofrequency current applications (duration 2082 ± 812 seconds) were delivered to achieve circumferential electrical isolation of pulmonary venous antra. Total procedural time reached 222 ± 54 minutes. The mean fluoroscopic time was 11.9 ± 7.8 minutes. There were no major procedure-related complications. After a median follow-up of 15 months (range 3-28 months), 63% of the patients were free from any atrial arrhythmias ≥ 30 seconds after the single procedure. Success rate increased to 86% after 1.2 procedures. Multivariate analysis revealed that only predictor of recurrent AF/AT was shorter overall procedural time (207 ± 36 vs 236 ± 64 minutes in patients with and without recurrences, respectively, P = 0.0068). This study demonstrates feasibility and safety of robotic navigation in catheter ablation for paroxysmal AF. Midterm follow-up documents success rate comparable to other technologies and potential for improvement in more extensive ablation along the ridges with thicker myocardium. © 2010 Wiley Periodicals, Inc.

  17. Atrial Fibrillation and Hyperthyroidism

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    Jayaprasad N

    2005-10-01

    Full Text Available Atrial fibrillation occurs in 10 – 15% of patients with hyperthyroidism. Low serum thyrotropin concentration is an independent risk factor for atrial fibrillation. Thyroid hormone contributes to arrythmogenic activity by altering the electrophysiological characteristics of atrial myocytes by shortening the action potential duration, enhancing automaticity and triggered activity in the pulmonary vein cardio myocytes. Hyperthyroidism results in excess mortality from increased incidence of circulatory diseases and dysrhythmias. Incidence of cerebral embolism is more in hyperthyroid patients with atrial fibrillation, especially in the elderly and anti-coagulation is indicated in them. Treatment of hyperthyroidism results in conversion to sinus rhythm in up to two-third of patients. Beta-blockers reduce left ventricular hypertrophy and atrial and ventricular arrhythmias in patients with hyperthyroidism. Treatment of sub clinical hyperthyroidism is controversial. Optimizing dose of thyroxine treatment in those with replacement therapy and beta-blockers is useful in exogenous subclinical hyperthyroidism.

  18. Electrical treatment of atrial arrhythmias in heart failure patients implanted with a dual defibrillator CRT device. Results from the TRADE-HF study.

    Science.gov (United States)

    Botto, Giovanni Luca; Padeletti, Luigi; Covino, Gregorio; Pieragnoli, Paolo; Liccardo, Mattia; Mariconti, Barbara; Favale, Stefano; Molon, Giulio; De Filippo, Paolo; Bolognese, Leonardo; Landolina, Maurizio; Raciti, Giovanni; Boriani, Giuseppe

    2017-06-01

    Ventricular and atrial arrhythmias commonly occur in heart failure patients and are a significant source of symptoms, morbidity and mortality. Some specific generators referred to as dual defibrillators, Dual CRT-Ds, have the ability to treat atrial and ventricular arrhythmias. TRADE-HF is a prospective two-arm randomized study aimed at assessing the benefits of complete automatic management of atrial arrhythmias in patients implanted with a dual CRT-D. Primary objective of the TRADE-HF study was to document reduction of unplanned hospital admission for cardiac reasons or death for cardiovascular causes or progression to permanent AF, by comparing fully-automatic device driven therapy for atrial tachycardia or fibrillation (AT/AF) to an in-hospital approach for treatment of symptomatic AT/AF. Randomized Patients were followed every 6months for 3years to assess the primary objective. Four-hundred-twenty patients have been enrolled in the study. At the end of the study 30 subjects died for cardiovascular causes, 60 had at least one hospitalization for cardiovascular causes and 14 developed permanent AF. Eighty-seven patients experienced a composite event. Hazard Ratio for device-managed automatic therapy arm compared to traditional was 0.987 (95% CI: 0.684-1.503; p=0.951). The primary endpoint analysis resulted in no difference between the device managed and in-hospital treatment arm. The TRADE-HF study failed to demonstrate a reduction in the composite of unplanned hospitalizations for cardiovascular causes or death for cardiovascular causes or progression to permanent AF using automatic atrial therapy compared to a traditional approach including hospitalization for symptomatic episodes and/or in-hospital treatment of AT/AF. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Randomized trial of atrial arrhythmia monitoring to guide anticoagulation in patients with implanted defibrillator and cardiac resynchronization devices

    NARCIS (Netherlands)

    Martin, David T.; Bersohn, Malcolm M.; Waldo, Albert L.; Wathen, Mark S.; Choucair, Wassim K.; Lip, Gregory Y. H.; Ip, John; Holcomb, Richard; Akar, Joseph G.; Halperin, Jonathan L.; Oosterwijk, Jan C.

    2015-01-01

    Aims Atrial tachyarrhythmias (ATs) detected by implanted devices are often atrial fibrillation or flutter (AF) associated with stroke. We hypothesized that introduction and termination of anticoagulation based upon AT monitoring would reduce both stroke and bleeding. Methods and results We

  20. Alcohol consumption, sinus tachycardia, and cardiac arrhythmias at the Munich Octoberfest: results from the Munich Beer Related Electrocardiogram Workup Study (MunichBREW).

    Science.gov (United States)

    Brunner, Stefan; Herbel, Rebecca; Drobesch, Cathrine; Peters, Annette; Massberg, Steffen; Kääb, Stefan; Sinner, Moritz F

    2017-07-14

    Alcohol is a risk factor for cardiac arrhythmias. Retrospective analyses suggest supraventricular arrhythmias consecutive to acute alcohol consumption, but prospective data are limited. We intended to prospectively associate acute alcohol consumption with cardiac arrhythmias. At the 2015 Munich Octoberfest, we enrolled 3028 voluntary participants who received a smartphone-based ECG and breath alcohol concentration (BAC) measurements. ECGs were analysed for cardiac arrhythmias (sinus tachycardia, sinus arrhythmia, premature atrial/ventricular complexes, atrial fibrillation/flutter) and respiratory sinus arrhythmia. By multivariable adjusted logistic regression we associated BACs with cardiac arrhythmias. Similarly, we analysed 4131 participants of the community-based KORA S4 Study (Co-operative Health Research in the Region of Augsburg) and associated cardiac arrhythmias with chronic alcohol consumption. In our acute alcohol cohort (mean age 34.4 ± 13.3 years, 29% women), mean BAC was 0.85 ± 0.54 g/kg. Cardiac arrhythmias occurred in 30.5% (sinus tachycardia 25.9%; other arrhythmia subtypes 5.4%). Breath alcohol concentration was significantly associated with cardiac arrhythmias overall (odds ratio (OR) per 1-unit change 1.75, 95% confidence interval (CI) 1.50-2.05; P cardiac arrhythmias and sinus tachycardia in particular. This partly reflects autonomic imbalance as assessed by significantly reduced respiratory sinus arrhythmia. Such imbalance might lead to sympathetically triggered atrial fibrillation resembling the holiday heart syndrome. NCT02550340.

  1. [Electrophysiologic evaluation of athletes with Wolff-Parkinson-White syndrome: induction of supraventricular arrhythmia at rest and under exertion with transesophageal atrial electrostimulation].

    Science.gov (United States)

    Vergara, G; Furlanello, F; Disertori, M; Bettini, R; Stirpe, E; Inama, G; Guarnerio, M; Cozzi, F; Visonà, L; Frisanco, L

    1986-08-01

    The most suitable approach to the athletes with WPW is controversial. Therefore 66 symptom-free athletes with WPW and without heart disease (53 M, 13 F, mean age 21.98 yrs, min 12--max 44) underwent a study protocol whose end-point was the induction of supraventricular tachyarrhythmia, i.e. atrial fibrillation or, if not possible, atrial flutter or atrial tachycardia at rest and during ergometric stress test. The athletes with shortest R-R interval between preexcited beats less than or equal to 240 ms at rest and/or less than or equal to 210 ms during exercise were judged as being at risk i.e. no fit for sport activity. The end-point was reached in 64/66 athletes (in 62 atrial fibrillation). In 4 athletes with life threatening arrhythmia induced at rest the evaluation during exercise was not performed. According to the evaluation at rest we were able to identify only 18 athletes (28.1%) as being at risk, while according to the complete study protocol 26 athletes (40.6%) were judged as such. In 23/64 athletes (36%) this judgement was discordant with the usual non invasive evaluation (i.e. Holter monitoring, ergometric stress test, ajmaline test). During induced atrial fibrillation no significant difference, was found between the percentage of preexcited beats at rest and during exercise. On the average, 40 min. are required for performance of this study protocol (if the induced arrhythmia lasts less than 5 min.). According to our results we conclude: a) the non invasive assessment of the WPW athletes is unsatisfactory; b) the induction of atrial fibrillation during exercise gives a remarkable increase of the diagnostic power with respect to the assessment only at rest; c) since it is simple to perform and not expensive (in time, staff and cost) and because of its high diagnostic yield, we regard this protocol as fundamental for the electrophysiological evaluation of WPW athletes and also suitable for systematic study of WPW patients.

  2. Role of subendocardial Purkinje network in triggering torsade de pointes arrhythmia in experimental long QT syndrome.

    Science.gov (United States)

    Ben Caref, E; Boutjdir, Mohamed; Himel, Herman D; El-Sherif, Nabil

    2008-10-01

    The present study addresses the controversy regarding the 'primary' role of the subendocardial Purkinje network in triggering torsade de pointes (TdP) ventricular tachyarrhythmia (VAs) in the long QT syndrome (LQTS). We investigated the well-established canine anthopleurin-A (AP-A) surrogate model of LQT3 to study the role of the subendocardial Purkinje network in triggering VAs. Three-dimensional activation and repolarization patterns were analysed from unipolar extracellular electrograms utilizing 64 plunge needle electrodes. In 6 dogs, the animals were placed on cardiopulmonary bypass and chemical ablation of the endocardial Purkinje network was obtained using Lugol's solution. Spontaneous VAs consistently developed in response to AP-A infusion and were triggered by a subendocardial focal activity acting on a substrate of spatial three-dimensional dispersion of repolarization. Endocardial ablation was considered successful by the development of complete atrioventricular block in the absence of ventricular escape rhythm. Following endocardial ablation spontaneous VAs were no longer observed. However, an appropriately coupled premature stimulus consistently induced re-entrant VAs. The present study strongly suggests that in the LQTS, focal activity generated in subendocardial Purkinje tissue is the primary, if not the only, trigger for TdP VAs by acting on a substrate of three-dimensional dispersion of myocardial repolarization to induce re-entrant excitation.

  3. Physical Activity Measured by Implanted Devices Predicts Atrial Arrhythmias and Patient Outcome: Results of IMPLANTED (Italian Multicentre Observational Registry on Patients With Implantable Devices Remotely Monitored).

    Science.gov (United States)

    Palmisano, Pietro; Guerra, Federico; Ammendola, Ernesto; Ziacchi, Matteo; Luigi Pisanò, Ennio Carmine; Dell'Era, Gabriele; Aspromonte, Vittorio; Zaccaria, Maria; Di Ubaldo, Francesco; Capucci, Alessandro; Nigro, Gerardo; Occhetta, Eraldo; Maglia, Giampiero; Ricci, Renato Pietro; Boriani, Giuseppe; Accogli, Michele

    2018-02-24

    To determine whether daily physical activity (PA), as measured by implanted devices (through accelerometer sensor), was related to the risk of developing atrial arrhythmias during long-term follow-up in a population of heart failure (HF) patients with an implantable cardioverter defibrillator (ICD). The study population was divided into 2 equally sized groups (PA cutoff point: 3.5 h/d) according to their mean daily PA recorded by the device during the 30- to 60-day period post-ICD implantation. Propensity score matching was used to compare 2 equally sized cohorts with similar characteristics between lower and higher activity patients. The primary end point was time free from the first atrial high-rate episode (AHRE) of duration ≥6 minutes. Secondary end points were: first AHRE ≥6 hours, first AHRE ≥48 hours, and a combined end point of death or HF hospitalization. Data from 770 patients (65±15 years; 66% men; left ventricular ejection fraction 35±12%) remotely monitored for a median of 25 months were analyzed. A PA ≥3.5 h/d was associated with a 38% relative reduction in the risk of AHRE ≥6 minutes (72-month cumulative survival: 75.0% versus 68.1%; log rank P =0.025), and with a reduction in the risk of AHRE ≥6 hours, AHRE ≥48 hours, and the combined end point of death or HF hospitalization (all P <0.05). In HF patients with ICD, a low level of daily PA was associated with a higher risk of atrial arrhythmias, regardless of the patients' baseline characteristics. In addition, a lower daily PA predicted death or HF hospitalization. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  4. [Arrhythmia and sleep apnea syndrome].

    Science.gov (United States)

    Marrakchi, S; Kammoun, I; Kachboura, S

    2015-10-01

    Arrhythmia is a major cause of morbidity and mortality in Europe and in the United States. The aim of this review article was to assess the results of the prospective studies that evaluated the risk of arrhythmia in patients with sleep apnea syndrome and discuss the management of this arrhythmia. Reports published with the following search terms were searched: sleep apnea syndrome, atrial flutter, supraventricular arrhythmia, ventricular arrhythmia, ventricular tachycardia, ventricular fibrillation, torsade de pointe, atrial fibrillation and sudden death. The investigation was restricted to reports published in English and French. The outcome of this analysis suggests that patients with untreated overt sleep apnea syndrome are at increased risk of arrhythmia. The timely recognition and effective treatment of sleep apnea syndrome in patients with arrhythmia are mandatory because the prognosis of arrhythmia may be improved with the appropriate treatment of sleep apnea syndrome. Copyright © 2015. Published by Elsevier Masson SAS.

  5. Echocardiography and cardiac arrhythmias.

    Science.gov (United States)

    Papadopoulos, Constantinos H; Oikonomidis, Dimitrios; Lazaris, Efstathios; Nihoyannopoulos, Petros

    2017-12-05

    Cardiac arrhythmias refer to any abnormality or disturbance in the normal activation sequence of the myocardium and may be indicative of structural heart disease and the cause of significant cardiovascular complications and sudden cardiac death. The following review summarizes the current state-of-the-art knowledge on the role of echocardiography in the management of cardiac arrhythmias and focuses on atrial fibrillation and ventricular arrhythmias where echocardiography presents a particular diagnostic and prognostic interest. Moreover, a brief reference is made to the effect of cardiac arrhythmias and conduction abnormalities on echocardiographic examination. Copyright © 2017 Hellenic Society of Cardiology. Published by Elsevier B.V. All rights reserved.

  6. Atrial fibrillation

    African Journals Online (AJOL)

    ABEOLUGBENGAS

    Objective: Atrial fibrillation is the commonest chronic arrhythmia and the etiology is widely varied. The aim of this study was to determine the etiology, clinical characteristics and treatment offered to adult patients with atrial fibrillation managed in a referral hospital in Port Harcourt, southern Nigeria. Methods:A retrospective ...

  7. Role of the autonomic nervous system in modulating cardiac arrhythmias.

    Science.gov (United States)

    Shen, Mark J; Zipes, Douglas P

    2014-03-14

    The autonomic nervous system plays an important role in the modulation of cardiac electrophysiology and arrhythmogenesis. Decades of research has contributed to a better understanding of the anatomy and physiology of cardiac autonomic nervous system and provided evidence supporting the relationship of autonomic tone to clinically significant arrhythmias. The mechanisms by which autonomic activation is arrhythmogenic or antiarrhythmic are complex and different for specific arrhythmias. In atrial fibrillation, simultaneous sympathetic and parasympathetic activations are the most common trigger. In contrast, in ventricular fibrillation in the setting of cardiac ischemia, sympathetic activation is proarrhythmic, whereas parasympathetic activation is antiarrhythmic. In inherited arrhythmia syndromes, sympathetic stimulation precipitates ventricular tachyarrhythmias and sudden cardiac death except in Brugada and J-wave syndromes where it can prevent them. The identification of specific autonomic triggers in different arrhythmias has brought the idea of modulating autonomic activities for both preventing and treating these arrhythmias. This has been achieved by either neural ablation or stimulation. Neural modulation as a treatment for arrhythmias has been well established in certain diseases, such as long QT syndrome. However, in most other arrhythmia diseases, it is still an emerging modality and under investigation. Recent preliminary trials have yielded encouraging results. Further larger-scale clinical studies are necessary before widespread application can be recommended.

  8. Early Detection of Symptomatic Paroxysmal Cardiac Arrhythmias by Trans-Telephonic ECG Monitoring: Impact on Diagnosis and Treatment of Atrial Fibrillation.

    Science.gov (United States)

    Anczykowski, Johanna; Willems, Stephan; Hoffmann, Boris A; Meinertz, Thomas; Blankenberg, Stefan; Patten, Monica

    2016-09-01

    Diagnosis of infrequent cardiac arrhythmias (CA) is often unsuccessful using resting or Holter ECG. As early detection and treatment of CA, especially atrial fibrillation (AF), has implications on patients' treatment and outcome, we investigated, whether self-guided, trans-telephonic event-recorder monitoring (Tele-ECG) improves diagnosis and influences treatment options. Between 2009 and 2014, 790 patients (54 ± 18 years, 40% male; no history of CA: 582, known AF: 179, other CA: 29) presented with recurrent symptoms suggestive of CA and were screened by Tele-ECG (17.3 ± 26.9 days). A total of 11,775 ECGs were transmitted via a 24-hour telephone hotline including documentation of the respective symptoms. In 73% of patients, CA was documented at the time of symptoms: sinus tachycardia 23%, premature ventricular beats 19%, AF 14%, supraventricular tachycardia 9%, sinus bradycardia 5%, sinus arrhythmia 2%, and AV block II 1%. The mean time until the first symptomatic episode occurred was 6.9 ± 15.3 days (median 2.5 days). The first documented arrhythmia occurred on average after 7.7 ± 14.1 days (median 3 days). In patients with AF (n = 110), 44% was newly diagnosed. According to the Tele-ECG diagnosis, AF ablation was performed in 27% of these patients, 7% electrical cardioversion, and in 30% antiarrhythmic therapy was initiated. In 65% of the patients with recurrence of known AF, (re-)ablation was performed or recommended and in 16% antiarrhythmic therapy was modified. Tele-ECG monitoring is effective in the diagnosis of suspected symptomatic CA. A diagnosis can usually be achieved within 1 week and has implications on patients' care. © 2016 Wiley Periodicals, Inc.

  9. Utilization and Clinical Feasibility of a Handheld Remote Electrocardiography Recording Device in Cardiac Arrhythmias and Atrial Fibrillation: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Wen-Ling Chang

    2015-12-01

    Conclusion: The handheld ECG device shows clinical feasibility with high rate for AF detection with a similar trend toward a higher prevalence with aging from different settings. These data suggested that portable ECG device via remote care system may aid in clinical diagnosis, therapeutic interventions, or patient referral for cardiac arrhythmias.

  10. Ganglionated plexi stimulation induces pulmonary vein triggers and promotes atrial arrhythmogenecity: In silico modeling study.

    Directory of Open Access Journals (Sweden)

    Minki Hwang

    Full Text Available The role of the autonomic nervous system (ANS on atrial fibrillation (AF is difficult to demonstrate in the intact human left atrium (LA due to technical limitations of the current electrophysiological mapping technique. We examined the effects of the ANS on the initiation and maintenance of AF by employing a realistic in silico human left atrium (LA model integrated with a model of ganglionated plexi (GPs.We incorporated the morphology of the GP and parasympathetic nerves in a three-dimensional (3D realistic LA model. For the model of ionic currents, we used a human atrial model. GPs were stimulated by increasing the IK[ACh], and sympathetic nerve stimulation was conducted through a homogeneous increase in the ICa-L. ANS-induced wave-dynamics changes were evaluated in a model that integrated a patient's LA geometry, and we repeated simulation studies using LA geometries from 10 different patients.The two-dimensional model of pulmonary vein (PV cells exhibited late phase 3 early afterdepolarization-like activity under 0.05μM acetylcholine (ACh stimulation. In the 3D simulation model, PV tachycardia was induced, which degenerated to AF via GP (0.05μM ACh and sympathetic (7.0×ICa-L stimulations. Under sustained AF, local reentries were observed at the LA-PV junction. We also observed that GP stimulation reduced the complex fractionated atrial electrogram (CFAE-cycle length (CL, p<0.01 and the life span of phase singularities (p<0.01. GP stimulation also increased the overlap area of the GP and CFAE areas (CFAE-CL≤120ms, p<0.01. When 3 patterns of virtual ablations were applied to the 3D AF models, circumferential PV isolation including the GP was the most effective in terminating AF.Cardiac ANS stimulations demonstrated triggered activity, automaticity, and local reentries at the LA-PV junction, as well as co-localized GP and CFAE areas in the 3D in silico GP model of the LA.

  11. Tachyarrhythmias triggered by swallowing and belching

    Science.gov (United States)

    Wilmshurst, P

    1999-01-01

    Three cases with supraventricular tachyarrhythmias related to oesophageal transit are reported. A 61 year old man had episodes of atrial tachycardia on each swallow of food but not liquid; this has been reported only rarely. A 55 year old man had atrial fibrillation initiated by drinking ice cold beverages; this has not been described previously although atrial tachycardia triggered by drinking ice cold beverages has been described once. A 68 year old man had supraventricular tachycardia initiated by belching; this has not been described previously. These cases illustrate the diversity of atrial tachyarrhythmias that can be precipitated by oesophageal stimulation and suggest that what is regarded as a very rare phenomenon may be found more commonly when sought.

 Keywords: atrial tachycardia; atrial fibrillation; deglutition; eructation; arrhythmias PMID:10026360

  12. Recommendations regarding dietary intake and caffeine and alcohol consumption in patients with cardiac arrhythmias: what do you tell your patients to do or not to do?

    Science.gov (United States)

    Glatter, Kathryn A; Myers, Richard; Chiamvimonvat, Nipavan

    2012-10-01

    The etiology of arrhythmias including atrial fibrillation is multifactorial. Most arrhythmias are associated with comorbid illnesses like hypertension, diabetes, thyroid disease, or advanced age. Although it is tempting to blame a stimulant like caffeine as a trigger for arrhythmias, the literature does not support this idea. There is no real benefit to having patients with arrhythmias limit their caffeine intake. Caffeine is a vasoactive substance that also may promote the release of norepinephrine and epinephrine. However, acute ingestion of caffeine (as coffee or tea) does not cause atrial fibrillation. Even patients suffering a myocardial infarction do not have an increased incidence of ventricular or other arrhythmias after ingesting several cups of coffee. Large epidemiologic studies have also failed to find a connection between the amount of coffee/caffeine used and the development of arrhythmias. As such, it does not make sense to suggest that patients with palpitations, paroxysmal atrial fibrillation, or supraventricular tachycardia, abstain from caffeine use. Energy drinks are a new phenomenon on the beverage market, with 30-50 % of young adults and teens using them regularly. Energy drinks are loaded with caffeine, sugar, and other chemicals that can stimulate the cardiac system. There is an increasing body of mainly anecdotal case reports describing arrhythmias or even sudden death triggered by exercise plus using energy drinks. Clearly, there must be more study in this area, but it is wise to either limit or avoid their use in patients with arrhythmias. Moderate to heavy alcohol use seems to be associated with the development of atrial fibrillation. The term "holiday heart" was coined back in 1978, to describe patients who had atrial fibrillation following binge alcohol use. Thus, it is reasonable to recommend to patients with arrhythmias that they limit their alcohol use, although unfortunately this treatment will likely not completely resolve their

  13. Impact of aortic encroachment to left atrium on non-pulmonary vein triggers of atrial fibrillation.

    Science.gov (United States)

    Allamsetty, Suresh; Lo, Li-Wei; Lin, Yenn-Jiang; Chang, Shih-Lin; Chung, Fa-Po; Hu, Yu-Feng; Lin, Chin-Yu; Chang, Yao-Ting; Chiang, Cheng-Hung; Huang, Hung-Kai; Chan, Chao-Shun; Do, Van Bun Dan; Lin, Chung-Hsing; Raharjo, Sunu; Jhuo, Shih-Jee; Walia, Rohit; Chen, Shih-Ann

    2017-01-15

    Aortic dilatation was frequently observed in patients with atrial fibrillation (AF) and non-pulmonary vein (PV) triggers are important for mapping and ablation of AF. We hypothesized that the aortic encroachment area over left atrium (LA) could contribute to the local substrate characteristics. We studied 32 consecutive patients of AF (age=57.34±8.07, male=30), including 26 paroxysmal and 6 persistent AFs. Anatomic relationship between LA and aorta, and electrophysiological characteristics of the encroachment areas were investigated. IRB approval was taken. The LA bipolar voltage (mean 0.49±0.26mV) was lower at aortic encroached area compared to global LA (mean 1.52±0.48mV) and it was statistically significant (pdistance from the aorta to the aortic encroachment area of LA (prelationship between LA and aorta is important during AF ablation for a better long term outcome. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. Hypertension and cardiac arrhythmias

    DEFF Research Database (Denmark)

    Lip, Gregory Y.H.; Coca, Antonio; Kahan, Thomas

    2017-01-01

    Hypertension is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease, stroke, peripheral artery disease and chronic renal insufficiency. Hypertensive heart disease can manifest as many cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both......, hypomagnesemia), further contributing to arrhythmias, whereas effective control of blood pressure may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between hypertension and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society...... supraventricular and ventricular arrhythmias may occur in hypertensive patients, especially in those with left ventricular hypertrophy (LVH) or HF. Also, some of the antihypertensive drugs commonly used to reduce blood pressure, such as thiazide diuretics, may result in electrolyte abnormalities (e.g. hypokalaemia...

  15. Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study

    Directory of Open Access Journals (Sweden)

    Fatima Dumas Cintra

    2014-11-01

    Full Text Available Background: The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea. Objective: To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample. Methods: Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart® system. Results: A total of 767 participants (461 men with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001. After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia. Conclusion: Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.

  16. A model of cardiac ryanodine receptor gating predicts experimental Ca2+-dynamics and Ca2+-triggered arrhythmia in the long QT syndrome

    Science.gov (United States)

    Wilson, Dan; Ermentrout, Bard; Němec, Jan; Salama, Guy

    2017-09-01

    Abnormal Ca2+ handling is well-established as the trigger of cardiac arrhythmia in catecholaminergic polymorphic ventricular tachycardia and digoxin toxicity, but its role remains controversial in Torsade de Pointes (TdP), the arrhythmia associated with the long QT syndrome (LQTS). Recent experimental results show that early afterdepolarizations (EADs) that initiate TdP are caused by spontaneous (non-voltage-triggered) Ca2+ release from Ca2+-overloaded sarcoplasmic reticulum (SR) rather than the activation of the L-type Ca2+-channel window current. In bradycardia and long QT type 2 (LQT2), a second, non-voltage triggered cytosolic Ca2+ elevation increases gradually in amplitude, occurs before overt voltage instability, and then precedes the rise of EADs. Here, we used a modified Shannon-Puglisi-Bers model of rabbit ventricular myocytes to reproduce experimental Ca2+ dynamics in bradycardia and LQT2. Abnormal systolic Ca2+-oscillations and EADs caused by SR Ca2+-release are reproduced in a modified 0-dimensional model, where 3 gates in series control the ryanodine receptor (RyR2) conductance. Two gates control RyR2 activation and inactivation and sense cytosolic Ca2+ while a third gate senses luminal junctional SR Ca2+. The model predicts EADs in bradycardia and low extracellular [K+] and cessation of SR Ca2+-release terminate salvos of EADs. Ca2+-waves, systolic cell-synchronous Ca2+-release, and multifocal diastolic Ca2+ release seen in subcellular Ca2+-mapping experiments are observed in the 2-dimensional version of the model. These results support the role of SR Ca2+-overload, abnormal SR Ca2+-release, and the subsequent activation of the electrogenic Na+/Ca2+-exchanger as the mechanism of TdP. The model offers new insights into the genesis of cardiac arrhythmia and new therapeutic strategies.

  17. Cardiac Arrhythmias in Recently Diagnosed Hypertensive Patients ...

    African Journals Online (AJOL)

    Various forms of cardiac arrhythmias have been documented in hypertensive subjects, and hypertension is an important risk factor for the development of atrial and ventricular arrhythmias and sudden death. Electrocardiography at rest easily documents significant arrhythmias in patients, and this study was carried out to ...

  18. Ranolazine Therapy in Cardiac Arrhythmias.

    Science.gov (United States)

    Pulford, Brian R; Kluger, Jeffrey

    2016-09-01

    Ranolazine is an antianginal medication originally granted approval by the U.S. Food and Drug Administration for therapeutic use in 2006. Since its introduction into the U.S. market, there have been multiple trials and clinical case reports that demonstrate ranolazine may be effective in the prevention and treatment of both atrial and ventricular arrhythmias, including postoperative atrial fibrillation following coronary artery bypass graft (CABG) surgery. More recently, the combination of dronedarone with ranolazine has demonstrated in initial studies to have a synergistic effect in the reduction of burden of atrial fibrillation. This article will review the basic pharmacology of ranolazine, the studies demonstrating use of ranolazine in atrial and ventricular arrhythmias, the limitations to the use of ranolazine as antiarrhythmic therapy, and explore the synergistic effect with other agents in the suppression of arrhythmias. © 2016 Wiley Periodicals, Inc.

  19. Hypertension and Cardiac Arrhythmias

    DEFF Research Database (Denmark)

    Lip, Gregory Y H; Coca, Antonio; Kahan, Thomas

    2017-01-01

    Hypertension (HTN) is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease (CAD), stroke, peripheral artery disease and chronic renal failure. Hypertensive heart disease can manifest as many types of cardiac arrhythmias, most commonly being atrial fibrillation......, hypomagnesaemia), contributing further to arrhythmias, while effective Blood pressure control may prevent the development of the arrhythmias such as AF.In recognizing this close relationship between HTN and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC......) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS) and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit of comprehensively reviewing the available evidence...

  20. [Arrhythmia and sport].

    Science.gov (United States)

    Saoudi, N; Yaici, K; Zarkane, N; Darmon, J P; Rinaldi, J P; Brunner, P; Ricard, P; Mourou, M Y

    2005-12-01

    Sports arrhythmia has gained wide attention with the mediatization of the death of famous sports stars. Sport strongly modifies the structure of the heart with the development of left ventricular hypertrophy which may be difficult to differentiate from that due to doping. Intense training modifies also the resting electrocardiogram with appearance of signs of left ventricular hypertrophy whereas resting sinus bradycardia and atrioventricular conduction disturbances usually reverts upon exertion. Accordingly, arrhythmia may develop ranging from extrasystoles to atrial fibrillation and even sudden death. Recent data suggest that if benign arrhythmia may be the result of the sole intense training and are reversible, malignant ventricular arrhythmia and sudden death mostly occur in unknown structural heart disease. Hypertrophic cardiomyopathy is amongst the most frequent post mortem diagnosis in this situation. Doping is now present in many sports and further threatens the athlete in the safe practice of sport.

  1. Atrial remodeling and atrial fibrillation: recent advances and translational perspectives.

    Science.gov (United States)

    Nattel, Stanley; Harada, Masahide

    2014-06-10

    Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice. AF and its complications are responsible for important population morbidity and mortality. Presently available therapeutic approaches have limited efficacy and nontrivial potential to cause adverse effects. Thus, new mechanistic knowledge is essential for therapeutic innovation. Atrial arrhythmogenic remodeling, defined as any change in atrial structure or function that promotes atrial arrhythmias, is central to AF. Remodeling can be due to underlying cardiac conditions, systemic processes and conditions such as aging, or AF itself. Recent work has underlined the importance of remodeling in AF, provided new insights into basic mechanisms, and identified new biomarker/imaging approaches to follow remodeling processes. The importance of intracellular Ca(2+) handling abnormalities has been highlighted, both for the induction of triggered ectopic activity and for the activation of Ca(2+)-related cell signaling that mediates profibrillatory remodeling. The importance of microRNAs, which are a new class of small noncoding sequences that regulate gene expression, has emerged in both electrical and structural remodeling. Remodeling related to aging, cardiac disease, and AF itself is believed to underlie the progressive nature of the arrhythmia, which contributes to the complexities of long-term management. New tools that are being developed to quantify remodeling processes and monitor their progression include novel biomarkers, imaging modalities to quantify/localize fibrosis, and noninvasive monitoring/mapping to better characterize the burden of AF and identify arrhythmic sources. This report reviews recent advances in the understanding of the basic pathophysiology of atrial remodeling and potential therapeutic implications. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  2. Atrial arrhythmias after lung and heart-lung transplant: effects on short-term mortality and the influence of amiodarone.

    Science.gov (United States)

    Isiadinso, Ijeoma; Meshkov, Arnold B; Gaughan, John; Sandhu, Paul; Lim, Sharon; Cordova, Francis; Criner, Gerard

    2011-01-01

    The incidence and effect of atrial fibrillation or flutter (AF) after lung transplant are variable. An effect of pharmacologic treatment on outcomes is undetermined. One hundred thirty-seven consecutive lung or heart-lung transplant patients were reviewed retrospectively. Uni- and multivariate analyses were performed to determine statistically significant risk factors for AF and short-term mortality. AF occurred in 45.0% of patients within 26 days. By univariate analysis, male gender was predictive of AF (hazard ratio [HR] = 2.25, 95% confidence interval [CI] 1.21 to 4.20, p = 0.011). Mortality within 200 days occurred in 36 of 137 (22.6%) patients. Those with AF had higher mortality than those without AF (27 of 62 [43.5%] vs 9 of 75 [12%]; p amiodarone died, whereas 3 of 26 (11.5%) patients treated without amiodarone died (p amiodarone (9 of 75 [12%] vs 3 of 26 [11.5%], p = 1.00). By multivariate analysis, chronic obstructive pulmonary disease (HR = 0.395, CI 0.175 to 0.892, p = 0.025), primary pulmonary hypertension (HR = 7.245, CI 1.89 to 27.84, p = 0.0039), and use of amiodarone (HR = 2.967, CI 1.187 to 7.415, p = 0.020) were associated with death. Amiodarone was shown to be a significant statistical moderator (p amiodarone. In patients with severe lung pathology, amiodarone pulmonary toxicity may be more common than previously known, and may be a significant contributor to mortality. Amiodarone use should be restricted in the lung transplant patient population. Copyright © 2011 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  3. Meta-analysis of randomized controlled trials on magnesium in addition to beta-blocker for prevention of postoperative atrial arrhythmias after coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Wu Xiaosan

    2013-01-01

    Full Text Available Abstract Background Atrial arrhythmia (AA is the most common complication after coronary artery bypass grafting (CABG. Only beta-blockers and amiodarone have been convincingly shown to decrease its incidence. The effectiveness of magnesium on this complication is still controversial. This meta-analysis was performed to evaluate the effect of magnesium as a sole or adjuvant agent in addition to beta-blocker on suppressing postoperative AA after CABG. Methods We searched the PubMed, Medline, ISI Web of Knowledge, Cochrane library databases and online clinical trial database up to May 2012. We used random effects model when there was significant heterogeneity between trials and fixed effects model when heterogeneity was negligible. Results Five randomized controlled trials were identified, enrolling a total of 1251 patients. The combination of magnesium and beta-blocker did not significantly decrease the incidence of postoperative AA after CABG versus beta-blocker alone (odds ratio (OR 1.12, 95% confidence interval (CI 0.86-1.47, P = 0.40. Magnesium in addition to beta-blocker did not significantly affect LOS (weighted mean difference −0.14 days of stay, 95% CI −0.58 to 0.29, P = 0.24 or the overall mortality (OR 0.59, 95% CI 0.08-4.56, P = 0.62. However the risk of postoperative adverse events was higher in the combination of magnesium and beta-blocker group than beta-blocker alone (OR 2.80, 95% CI 1.66-4.71, P = 0.0001. Conclusions This meta-analysis offers the more definitive evidence against the prophylactic administration of intravenous magnesium for prevention of AA after CABG when beta-blockers are routinely administered, and shows an association with more adverse events in those people who received magnesium.

  4. Electrophysiological Mechanisms of Atrial Flutter

    Directory of Open Access Journals (Sweden)

    Ching- Tai Tai

    2006-04-01

    Full Text Available Atrial flutter (AFL is a common arrhythmia in clinical practice. Several experimental models such as tricuspid regurgitation model, tricuspid ring model, sterile pericarditis model and atrial crush injury model have provided important information about reentrant circuit and can test the effect of antiarrhythmic drugs. Human atrial flutter has typical and atypical forms. Typical atrial flutter rotates around tricuspid annulus and uses the crista terminalis and sometimes sinus venosa as the boundary. The IVC-tricuspid isthmus is a slow conduction zone and the target of radiofrequency ablation. Atypical atrial flutter may arise from the right or left atrium. Right atrial flutter includes upper loop reentry, free wall reentry and figure of eight reentry. Left atrial flutter includes mitral annular atrial flutter, pulmonary vein-related atrial flutter and left septal atrial flutter. Radiofrequency ablation of the isthmus between the boundaries can eliminate these arrhythmias.

  5. Ambulatory Cardiac Monitoring for Discharged Emergency Department Patients with Possible Cardiac Arrhythmias

    Directory of Open Access Journals (Sweden)

    Donald Scheiber

    2014-03-01

    Full Text Available Introduction: Many emergency department (ED patients have symptoms that may be attributed to arrhythmias, necessitating outpatient ambulatory cardiac monitoring. Consensus is lacking on the optimal duration of monitoring. We describe the use of a novel device applied at ED discharge that provides continuous prolonged cardiac monitoring. Methods: We enrolled discharged adult ED patients with symptoms of possible cardiac arrhythmia. A novel, single use continuous recording patch (Zio®Patch was applied at ED discharge. Patients wore the device for up to 14 days or until they had symptoms to trigger an event. They then returned the device by mail for interpretation. Significant arrhythmias are defined as: ventricular tachycardia (VT ≥4 beats, supraventricular tachycardia (SVT ≥4 beats, atrial fibrillation, ≥3 second pause, 2nd degree Mobitz II, 3rd degree AV Block, or symptomatic bradycardia. Results: There were 174 patients were enrolled and all mailed back their devices. The average age was 52.2 (± 21.0 years, and 55% were female. The most common indications for device placement were palpitations 44.8%, syncope 24.1% and dizziness 6.3%. Eighty-three patients (47.7% had ≥1 arrhythmias and 17 (9.8% were symptomatic at the time of their arrhythmia. Median time to first arrhythmia was 1.0 days (IQR 0.2-2.8 and median time to first symptomatic arrhythmia was 1.5 days (IQR 0.4-6.7. 93 (53.4% of symptomatic patients did not have any arrhythmia during their triggered events. The overall diagnostic yield was 63.2% Conclusion: The Zio®Patch cardiac monitoring device can efficiently characterize symptomatic patients without significant arrhythmia and has a higher diagnostic yield for arrhythmias than traditional 24-48 hour Holter monitoring. It allows for longer term monitoring up to 14 days. [West J Emerg Med. 2014;15(2:194–198.

  6. Autoantibodies and Cardiac Arrhythmias

    Science.gov (United States)

    Lee, Hon-Chi; Huang, Kristin T. L.; Wang, Xiao-Li; Shen, Win-Kuang

    2013-01-01

    Autoimmune diseases are associated with significant morbidity and mortality, afflicting about 5% of the population of the United States. They encompass a wide range of disorders that affect all organs of the human body and have a predilection for women. In the past, autoimmune pathogenesis was not thought to be a major mechanism for cardiovascular disorders, and potential relationships remain understudied. However, accumulating evidence suggests that a number of vascular and cardiac conditions are autoimmune-mediated. Recent studies indicate that autoantibodies play an important role in the development of cardiac arrhythmias, including atrial fibrillation, modulation of autonomic influences on heart rate and rhythm, conduction system abnormalities, and ventricular arrhythmias. This manuscript will review the current evidence for the role of autoantibodies in the development of cardiac arrhythmias. PMID:21740882

  7. Atrioverter : An implantable device for the treatment of atrial fibrillation

    NARCIS (Netherlands)

    Wellens, HJJ; Lau, CP; Luderitz, B; Akhtar, M; Waldo, AL; Camm, AJ; Timmermans, C; Tse, HF; Jung, W; Jordaens, L; Ayers, G

    1998-01-01

    Background-During atrial fibrillation, electrophysiological changes occur in atrial tissue that favor the maintenance of the arrhythmia and facilitate recurrence after conversion to sinus rhythm. An implantable defibrillator connected to right atrial and coronary sinus defibrillation leads allows

  8. Atrial fibrillation: non cardiologist physicians approach

    Directory of Open Access Journals (Sweden)

    Forero-Gómez, Julián Eduardo

    2017-10-01

    Full Text Available Atrial fibrillation is the most frequent arrhythmia. Its classification according to pattern and clinical type allows to decide the therapeutic strategy to use, that most include control of symptoms and prevention of cardioembolic events. The election of the treatment depends on the presence of triggering events, risk factors for thromboembolism, risk factors for bleeding, cardiac function, patient funcionality, medication costoefectiveness and health care access. The type of anticoagulant has to be supported on the type of atrial fibrillation and the presence of contraindications, documented ineffective anticoagulation or high risk of failure to warfarin. In case of contraindications for anticoagulation this could still be used in high bleeding risk patients, when risk factors are controllable or corrected; leaving left atrial appendage closure as an option for patients that remain in high risk for bleeding events.

  9. Aconitine-induced Ca{sup 2+} overload causes arrhythmia and triggers apoptosis through p38 MAPK signaling pathway in rats

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Gui-bo; Sun, Hong; Meng, Xiang-bao [Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193 (China); Hu, Jin; Zhang, Qiang; Liu, Bo [Academy of Chinese Medical Sciences of Jilin Province, Changchun, Jilin 130021 (China); Wang, Min [Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193 (China); Xu, Hui-bo, E-mail: xhb_6505@163.com [Academy of Chinese Medical Sciences of Jilin Province, Changchun, Jilin 130021 (China); Sun, Xiao-bo, E-mail: sun_xiaobo163@163.com [Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193 (China)

    2014-08-15

    {sup 2+} overload causes arrhythmia in rats. • Aconitine induces Ca{sup 2+} overload through the activation of L-type Ca{sup 2+} channels. • Aconitine-induced Ca{sup 2+} overload triggers apoptotic responses in vitro and in vivo. • Aconitine promotes apoptotic development via activation of P38 MAPK.

  10. Atrial fibrillation in KCNE1-null mice

    NARCIS (Netherlands)

    Temple, Joel; Frias, Patricio; Rottman, Jeffrey; Yang, Tao; Wu, Yuejin; Verheijck, E. Etienne; Zhang, Wei; Siprachanh, Chanthaphaychith; Kanki, Hideaki; Atkinson, James B.; King, Paul; Anderson, Mark E.; Kupershmidt, Sabina; Roden, Dan M.

    2005-01-01

    Although atrial fibrillation is the most common serious cardiac arrhythmia, the fundamental molecular pathways remain undefined. Mutations in KCNQ1, one component of a sympathetically activated cardiac potassium channel complex, cause familial atrial fibrillation, although the mechanisms in vivo are

  11. Arrhythmias in Heart Failure.

    Science.gov (United States)

    Auricchio; Klein

    2000-08-01

    Cardiac arrhythmias are very common in the setting of heart failure, with atrial and ventricular arrhythmias often present in the same patient. The risk and the benefit of antiarrhythmic therapies are still a matter of debate. Class I antiarrhythmic drugs should be avoided in patients with heart failure, cardiac ischemia, or previous myocardial infarction. Beta-blocker agents reduce morbidity and decrease mortality in patients suffering from moderate to severe heart failure. Amiodarone may be beneficial in patients with advanced heart failure and increased resting heart rates. This class III drug may be effective to suppress episodes of atrial fibrillation but can also be beneficial in reducing ventricular response by slowing atrioventricular conduction during chronic atrial fibrillation. Implantable cardioverter-defibrillators (ICDs) markedly reduce sudden cardiac death in patients with ventricular tachycardia or ventricular fibrillation. In patients with advanced heart failure, however, the ICD may not markedly extend survival. Recently analyzed data from the Canadian Implantable Defibrillator Study (CIDS), Antiarrhythmics Versus Implantable Defibrillators (AVID) registry, Multicenter Unsustained Tachycardia Trial (MUSTT), and Multicenter Automatic Defibrillator Implantation Trial (MADIT) have consistently shown that it is the sickest patient who benefits the most from ICD therapy. Patients with markedly depressed ejection fraction (death will translate into a reduction of all-cause mortality. For patients resuscitated from sustained ventricular tachycardia or ventricular fibrillation, an ICD or, in some cases, amiodarone should be considered. Catheter or surgical ablation can be considered for selected patients with ventricular tachycardia.

  12. TRIGGER

    CERN Multimedia

    Wesley Smith

    Level-1 Trigger Hardware and Software The hardware of the trigger components has been mostly finished. The ECAL Endcap Trigger Concentrator Cards (TCC) are in production while Barrel TCC firmware has been upgraded, and the Trigger Primitives can now be stored by the Data Concentrator Card for readout by the DAQ. The Regional Calorimeter Trigger (RCT) system is complete, and the timing is being finalized. All 502 HCAL trigger links to RCT run without error. The HCAL muon trigger timing has been equalized with DT, RPC, CSC and ECAL. The hardware and firmware for the Global Calorimeter Trigger (GCT) jet triggers are being commissioned and data from these triggers is available for readout. The GCT energy sums from rings of trigger towers around the beam pipe beam have been changed to include two rings from both sides. The firmware for Drift Tube Track Finder, Barrel Sorter and Wedge Sorter has been upgraded, and the synchronization of the DT trigger is satisfactory. The CSC local trigger has operated flawlessly u...

  13. TRIGGER

    CERN Multimedia

    Roberta Arcidiacono

    2013-01-01

    Trigger Studies Group (TSG) The Trigger Studies Group has just concluded its third 2013 workshop, where all POGs presented the improvements to the physics object reconstruction, and all PAGs have shown their plans for Trigger development aimed at the 2015 High Level Trigger (HLT) menu. The Strategy for Trigger Evolution And Monitoring (STEAM) group is responsible for Trigger menu development, path timing, Trigger performance studies coordination, HLT offline DQM as well as HLT release, menu and conditions validation – this last task in collaboration with PdmV (Physics Data and Monte Carlo Validation group). In the last months the group has delivered several HLT rate estimates and comparisons, using the available data and Monte Carlo samples. The studies were presented at the Trigger workshops in September and December, and STEAM has contacted POGs and PAGs to understand the origin of the discrepancies observed between 8 TeV data and Monte Carlo simulations. The most recent results show what the...

  14. Triggers

    NARCIS (Netherlands)

    Breitbarth, A.; van Riemsdijk, H.C.

    2004-01-01

    The concept of 'trigger' is a core concept of Chomsky's Minimalist Program. The idea that certain types of movement are triggered by some property of the target position is at least as old as the notion that the movement of noun phrases to the subject position is triggered by their need to receive

  15. Substrate and Trigger Ablation for Reduction of Atrial Fibrillation (STAR AF): a randomized, multicentre, international trial†

    Science.gov (United States)

    Verma, Atul; Mantovan, Roberto; Macle, Laurent; De Martino, Guiseppe; Chen, Jian; Morillo, Carlos A.; Novak, Paul; Calzolari, Vittorio; Guerra, Peter G.; Nair, Girish; Torrecilla, Esteban G.; Khaykin, Yaariv

    2010-01-01

    Aims This multicentre, randomized trial compared three strategies of AF ablation: ablation of complex fractionated electrograms (CFE) alone, pulmonary vein isolation (PVI) alone, and combined PVI + CFE ablation, using standardized automated mapping software. Methods and results Patients with drug-refractory, high-burden paroxysmal (episodes >6 h, >4 in 6 months) or persistent atrial fibrillation (AF) were enrolled at eight centres. Patients (n = 100) were randomized to one of three arms. For CFE alone (n = 34), spontaneous/induced AF was mapped using validated, automated CFE software and all sites 30 s at 1 year. Patients (age 57 ± 10 years, LA size 42 ± 6 mm) were 35% persistent AF. In CFE, ablation terminated AF in 68%. Only 0.4 PVs per patient were isolated as a result of CFE. In PVI, 94% had all four PVs successfully isolated. In PVI + CFE, 94% had all four PVs isolated, 76% had inducible AF with additional CFE ablation, with 73% termination of AF. There were significantly more repeat procedures in the CFE arm (47%) vs. PVI (31%) or PVI + CFE (15%) (P = 0.01). After one procedure, PVI + CFE had a significantly higher freedom from AF (74%) compared with PVI (48%) and CFE (29%) (P = 0.004). After two procedures, PVI + CFE still had the highest success (88%) compared with PVI (68%) and CFE (38%) (P = 0.001). Ninety-six percent of these patients were off anti-arrhythmics. Complications were two tamponades, no PV stenosis, and no mortality. Conclusion In high-burden paroxysmal/persistent AF, PVI + CFE has the highest freedom from AF vs. PVI or CFE alone after one or two procedures. Complex fractionated electrogram alone has the lowest one and two procedure success rates with a higher incidence of repeat procedures. ClinicalTrials.gov identifier number NCT00367757. PMID:20215126

  16. TRIGGER

    CERN Multimedia

    Wesley Smith

    Level-1 Trigger Hardware and Software The trigger synchronization procedures for running with cosmic muons and operating with the LHC were reviewed during the May electronics week. Firmware maintenance issues were also reviewed. Link tests between the new ECAL endcap trigger concentrator cards (TCC48) and the Regional Calorimeter Trigger have been performed. Firmware for the energy sum triggers and an upgraded tau trigger of the Global Calorimeter Triggers has been developed and is under test. The optical fiber receiver boards for the Track-Finder trigger theta links of the DT chambers are now all installed. The RPC trigger is being made more robust by additional chamber and cable shielding and also by firmware upgrades. For the CSC’s the front-end and trigger motherboard firmware have been updated. New RPC patterns and DT/CSC lookup tables taking into account phi asymmetries in the magnetic field configuration are under study. The motherboard for the new pipeline synchronizer of the Global Trigg...

  17. TRIGGER

    CERN Multimedia

    W. Smith

    2012-01-01

      Level-1 Trigger The Level-1 Trigger group is ready to deploy improvements to the L1 Trigger algorithms for 2012. These include new high-PT patterns for the RPC endcap, an improved CSC PT assignment, a new PT-matching algorithm for the Global Muon Trigger, and new calibrations for ECAL, HCAL, and the Regional Calorimeter Trigger. These should improve the efficiency, rate, and stability of the L1 Trigger. The L1 Trigger group also is migrating the online systems to SLC5. To make the data transfer from the Global Calorimeter Trigger to the Global Trigger more reliable and also to allow checking the data integrity online, a new optical link system has been developed by the GCT and GT groups and successfully tested at the CMS electronics integration facility in building 904. This new system is now undergoing further tests at Point 5 before being deployed for data-taking this year. New L1 trigger menus have recently been studied and proposed by Emmanuelle Perez and the L1 Detector Performance Group...

  18. TRIGGER

    CERN Multimedia

    W. Smith

    At the March meeting, the CMS trigger group reported on progress in production, tests in the Electronics Integration Center (EIC) in Prevessin 904, progress on trigger installation in the underground counting room at point 5, USC55, the program of trigger pattern tests and vertical slice tests and planning for the Global Runs starting this summer. The trigger group is engaged in the final stages of production testing, systems integration, and software and firmware development. Most systems are delivering final tested electronics to CERN. The installation in USC55 is underway and integration testing is in full swing. A program of orderly connection and checkout with subsystems and central systems has been developed. This program includes a series of vertical subsystem slice tests providing validation of a portion of each subsystem from front-end electronics through the trigger and DAQ to data captured and stored. After full checkout, trigger subsystems will be then operated in the CMS Global Runs. Continuous...

  19. Mapping strategy for multiple atrial tachyarrhythmias in a transplant heart

    DEFF Research Database (Denmark)

    Jin, Qi; Pehrson, Steen; Jacobsen, Peter Karl

    2015-01-01

    BACKGROUND: Different atrial arrhythmias can coexist in the recipient and donor atria after heart transplantation. CASE PRESENTATION: We report an unusual case of a patient with three different types of atrial arrhythmia after heart transplantation: an atrial fibrillation in the recipient atria, ...

  20. TRIGGER

    CERN Multimedia

    Wesley Smith

    Level-1 Trigger Hardware and Software The production of the trigger hardware is now basically finished, and in time for the turn-on of the LHC. The last boards produced are the Trigger Concentrator Cards for the ECAL Endcaps (TCC-EE). After the recent installation of the four EE Dees, the TCC-EE prototypes were used for their commissioning. Production boards are arriving and are being tested continuously, with the last ones expected in November. The Regional Calorimeter Trigger hardware is fully integrated after installation of the last EE cables. Pattern tests from the HCAL up to the GCT have been performed successfully. The HCAL triggers are fully operational, including the connection of the HCAL-outer and forward-HCAL (HO/HF) technical triggers to the Global Trigger. The HCAL Trigger and Readout (HTR) board firmware has been updated to permit recording of the tower “feature bit” in the data. The Global Calorimeter Trigger hardware is installed, but some firmware developments are still n...

  1. TRIGGER

    CERN Multimedia

    by Wesley Smith

    2010-01-01

    Level-1 Trigger Hardware and Software The overall status of the L1 trigger has been excellent and the running efficiency has been high during physics fills. The timing is good to about 1%. The fine-tuning of the time synchronization of muon triggers is ongoing and will be completed after more than 10 nb-1 of data have been recorded. The CSC trigger primitive and RPC trigger timing have been refined. A new configuration for the CSC Track Finder featured modified beam halo cuts and improved ghost cancellation logic. More direct control was provided for the DT opto-receivers. New RPC Cosmic Trigger (RBC/TTU) trigger algorithms were enabled for collision runs. There is further work planned during the next technical stop to investigate a few of the links from the ECAL to the Regional Calorimeter Trigger (RCT). New firmware and a new configuration to handle trigger rate spikes in the ECAL barrel are also being tested. A board newly developed by the tracker group (ReTRI) has been installed and activated to block re...

  2. TRIGGER

    CERN Multimedia

    W. Smith

    2010-01-01

    Level-1 Trigger Hardware and Software The Level-1 Trigger hardware has performed well during both the recent proton-proton and heavy ion running. Efforts were made to improve the visibility and handling of alarms and warnings. The tracker ReTRI boards that prevent fixed frequencies of Level-1 Triggers are now configured through the Trigger Supervisor. The Global Calorimeter Trigger (GCT) team has introduced a buffer cleanup procedure at stops and a reset of the QPLL during configuring to ensure recalibration in case of a switch from the LHC clock to the local clock. A device to test the cables between the Regional Calorimeter Trigger and the GCT has been manufactured. A wrong charge bit was fixed in the CSC Trigger. The ECAL group is improving crystal masking and spike suppression in the trigger primitives. New firmware for the Drift Tube Track Finder (DTTF) sorters was developed to improve fake track tagging and sorting. Zero suppression was implemented in the DT Sector Collector readout. The track finder b...

  3. TRIGGER

    CERN Multimedia

    Wesley Smith

    Trigger Hardware The status of the trigger components was presented during the September CMS Week and Annual Review and at the monthly trigger meetings in October and November. Procedures for cold and warm starts (e.g. refreshing of trigger parameters stored in registers) of the trigger subsystems have been studied. Reviews of parts of the Global Calorimeter Trigger (GCT) and the Global Trigger (GT) have taken place in October and November. The CERN group summarized the status of the Trigger Timing and Control (TTC) system. All TTC crates and boards are installed in the underground counting room, USC55. The central clock system will be upgraded in December (after the Global Run at the end of November GREN) to the new RF2TTC LHC machine interface timing module. Migration of subsystem's TTC PCs to SLC4/ XDAQ 3.12 is being prepared. Work is on going to unify the access to Local Timing Control (LTC) and TTC CMS interface module (TTCci) via SOAP (Simple Object Access Protocol, a lightweight XML-based messaging ...

  4. TRIGGER

    CERN Multimedia

    W. Smith from contributions of C. Leonidopoulos

    2010-01-01

    Level-1 Trigger Hardware and Software Since nearly all of the Level-1 (L1) Trigger hardware at Point 5 has been commissioned, activities during the past months focused on the fine-tuning of synchronization, particularly for the ECAL and the CSC systems, on firmware upgrades and on improving trigger operation and monitoring. Periodic resynchronizations or hard resets and a shortened luminosity section interval of 23 seconds were implemented. For the DT sector collectors, an automatic power-off was installed in case of high temperatures, and the monitoring capabilities of the opto-receivers and the mini-crates were enhanced. The DTTF and the CSCTF now have improved memory lookup tables. The HCAL trigger primitive logic implemented a new algorithm providing better stability of the energy measurement in the presence of any phase misalignment. For the Global Calorimeter Trigger, additional Source Cards have been manufactured and tested. Testing of the new tau, missing ET and missing HT algorithms is underw...

  5. Operative techniques in association with arrhythmia surgery in patients with congenital heart disease.

    Science.gov (United States)

    Mavroudis, Constantine; Deal, Barbara; Backer, Carl L; Stewart, Robert D

    2013-01-01

    Arrhythmia surgery in patients with congenital disease is challenged by the range of anatomic variants, arrhythmia types, and intramyocardial scar location. Experimental and clinical studies have elucidated the mechanisms of arrhythmias for accessory connections, atrial fibrillation, atrial reentry tachycardia, nodal reentry tachycardia, focal or automatic atrial tachycardia, and ventricular tachycardia. The surgical and transcatheter possibilities are numerous, and the congenital heart surgeon should have a comprehensive understanding of all arrhythmia types and potential methods of ablation. The purpose of this article is to introduce resternotomy techniques for safe mediastinal reentry and to review operative techniques of arrhythmia surgery in association with congenital heart disease.

  6. Occurrence of cardiac arrhythmias in Standardbred racehorses.

    Science.gov (United States)

    Slack, J; Boston, R C; Soma, L R; Reef, V B

    2015-07-01

    Cardiac arrhythmias are a recognised but poorly characterised problem in the Standardbred racehorse. Frequency data could aid the development of cardiac arrhythmia screening programmes. To characterise the occurrence of cardiac arrhythmias in Standardbreds prior to racing and in the late post race period using a handheld, noncontinuous recording device. Prospective, observational study, convenience sampling. Noncontinuous electrocardiographic recordings were obtained over a 12 week period from Standardbred horses competing at a single racetrack. Electrocardiograms were obtained before racing and between 6 and 29 min after the race using a handheld recording device. Prevalence of arrhythmias was calculated for all horses and overall frequency of arrhythmias was calculated for race starts and poor performers. Univariate logistic regression analysis was used to identify risk factors for cardiac arrhythmias. A total of 8657 electrocardiogram recordings were obtained from 1816 horses. Six horses had atrial fibrillation after racing (prevalence = 0.11%, frequency = 0.14%), one horse had supraventricular tachycardia before racing (prevalence = 0.06%, frequency = 0.02%), and 2 horses had ventricular tachyarrhythmias after racing (prevalence = 0.06%, frequency = 0.05%). The frequency of atrial fibrillation among race starts with poor performance was 1.3-2.0%. Increasing age was a significant risk factor for the presence of atrial premature contractions before racing and atrial fibrillation and ventricular ectopy after racing. Both physiological and pathological cardiac arrhythmias can be detected in apparently healthy Standardbred horses in the prerace and late post race period using noncontinuous recording methods. Future studies should examine cumulative training or racing hours as a risk factor for cardiac arrhythmia. The prevalence and frequency information may be useful for track veterinarians and regulatory personnel following trends in cardiac arrhythmias. © 2014

  7. TRIGGER

    CERN Multimedia

    Wesley Smith

    Level-1 Trigger Hardware and Software The final parts of the Level-1 trigger hardware are now being put in place. For the ECAL endcaps, more than half of the Trigger Concentrator Cards for the ECAL Endcap (TCC-EE) are now available at CERN, such that one complete endcap can be covered. The Global Trigger now correctly handles ECAL calibration sequences, without being influenced by backpressure. The Regional Calorimeter Trigger (RCT) hardware is complete and working in USC55. Intra-crate tests of all 18 RCT crates and the Global Calorimeter Trigger (GCT) are regularly taking place. Pattern tests have successfully captured data from HCAL through RCT to the GCT Source Cards. HB/HE trigger data are being compared with emulator results to track down the very few remaining hardware problems. The treatment of hot and dead cells, including their recording in the database, has been defined. For the GCT, excellent agreement between the emulator and data has been achieved for jets and HF ET sums. There is still som...

  8. TRIGGER

    CERN Multimedia

    W. Smith

    Level-1 Trigger Hardware and Software The trigger system has been constantly in use in cosmic and commissioning data taking periods. During CRAFT running it delivered 300 million muon and calorimeter triggers to CMS. It has performed stably and reliably. During the abort gaps it has also provided laser and other calibration triggers. Timing issues, namely synchronization and latency issues, have been solved. About half of the Trigger Concentrator Cards for the ECAL Endcap (TCC-EE) are installed, and the firmware is being worked on. The production of the other half has started. The HCAL Trigger and Readout (HTR) card firmware has been updated, and new features such as fast parallel zero-suppression have been included. Repairs of drift tube (DT) trigger mini-crates, optical links and receivers of sector collectors are under way and have been completed on YB0. New firmware for the optical receivers of the theta links to the drift tube track finder is being installed. In parallel, tests with new eta track finde...

  9. TRIGGER

    CERN Multimedia

    R. Carlin with contributions from D. Acosta

    2012-01-01

    Level-1 Trigger Data-taking continues at cruising speed, with high availability of all components of the Level-1 trigger. We have operated the trigger up to a luminosity of 7.6E33, where we approached 100 kHz using the 7E33 prescale column.  Recently, the pause without triggers in case of an automatic "RESYNC" signal (the "settle" and "recover" time) was reduced in order to minimise the overall dead-time. This may become very important when the LHC comes back with higher energy and luminosity after LS1. We are also preparing for data-taking in the proton-lead run in early 2013. The CASTOR detector will make its comeback into CMS and triggering capabilities are being prepared for this. Steps to be taken include improved cooperation with the TOTEM trigger system and using the LHC clock during the injection and ramp phases of LHC. Studies are being finalised that will have a bearing on the Trigger Technical Design Report (TDR), which is to be rea...

  10. TRIGGER

    CERN Multimedia

    W. Smith

    At the December meeting, the CMS trigger group reported on progress in production, tests in the Electronics Integration Center (EIC) in Prevessin 904, progress on trigger installation in the underground counting room at point 5, USC55, and results from the Magnet Test and Cosmic Challenge (MTCC) phase II. The trigger group is engaged in the final stages of production testing, systems integration, and software and firmware development. Most systems are delivering final tested electronics to CERN. The installation in USC55 is underway and moving towards integration testing. A program of orderly connection and checkout with subsystems and central systems has been developed. This program includes a series of vertical subsystem slice tests providing validation of a portion of each subsystem from front-end electronics through the trigger and DAQ to data captured and stored. This is combined with operations and testing without beam that will continue until startup. The plans for start-up, pilot and early running tri...

  11. TRIGGER

    CERN Multimedia

    Wesley Smith

    2011-01-01

    Level-1 Trigger Hardware and Software New Forward Scintillating Counters (FSC) for rapidity gap measurements have been installed and integrated into the Trigger recently. For the Global Muon Trigger, tuning of quality criteria has led to improvements in muon trigger efficiencies. Several subsystems have started campaigns to increase spares by recovering boards or producing new ones. The barrel muon sector collector test system has been reactivated, new η track finder boards are in production, and φ track finder boards are under revision. In the CSC track finder, an η asymmetry problem has been corrected. New pT look-up tables have also improved efficiency. RPC patterns were changed from four out of six coincident layers to three out of six in the barrel, which led to a significant increase in efficiency. A new PAC firmware to trigger on heavy stable charged particles allows looking for chamber hit coincidences in two consecutive bunch-crossings. The redesign of the L1 Trigger Emulator...

  12. TRIGGER

    CERN Document Server

    W. Smith from contributions of C. Leonidopoulos, I. Mikulec, J. Varela and C. Wulz.

    Level-1 Trigger Hardware and Software Over the past few months, the Level-1 trigger has successfully recorded data with cosmic rays over long continuous stretches as well as LHC splash events, beam halo, and collision events. The L1 trigger hardware, firmware, synchronization, performance and readiness for beam operation were reviewed in October. All L1 trigger hardware is now installed at Point 5, and most of it is completely commissioned. While the barrel ECAL Trigger Concentrator Cards are fully operational, the recently delivered endcap ECAL TCC system is still being commissioned. For most systems there is a sufficient number of spares available, but for a few systems additional reserve modules are needed. It was decided to increase the overall L1 latency by three bunch crossings to increase the safety margin for trigger timing adjustments. In order for CMS to continue data taking during LHC frequency ramps, the clock distribution tree needs to be reset. The procedures for this have been tested. A repl...

  13. TRIGGER

    CERN Multimedia

    W. Smith

    Level-1 Trigger Hardware and Software The road map for the final commissioning of the level-1 trigger system has been set. The software for the trigger subsystems is being upgraded to run under CERN Scientific Linux 4 (SLC4). There is also a new release for the Trigger Supervisor (TS 1.4), which implies upgrade work by the subsystems. As reported by the CERN group, a campaign to tidy the Trigger Timing and Control (TTC) racks has begun. The machine interface was upgraded by installing the new RF2TTC module, which receives RF signals from LHC Point 4. Two Beam Synchronous Timing (BST) signals, one for each beam, can now be received in CMS. The machine group will define the exact format of the information content shortly. The margin on the locking range of the CMS QPLL is planned for study for different subsystems in the next Global Runs, using a function generator. The TTC software has been successfully tested on SLC4. Some TTC subsystems have already been upgraded to SLC4. The TTCci Trigger Supervisor ...

  14. TRIGGER

    CERN Multimedia

    W. Smith, from contributions of D. Acosta

    2012-01-01

      The L1 Trigger group deployed several major improvements this year. Compared to 2011, the single-muon trigger rate has been reduced by a factor of 2 and the η coverage has been restored to 2.4, with high efficiency. During the current technical stop, a higher jet seed threshold will be applied in the Global Calorimeter Trigger in order to significantly reduce the strong pile-up dependence of the HT and multi-jet triggers. The currently deployed L1 menu, with the “6E33” prescales, has a total rate of less than 100 kHz and operates with detector readout dead time of less than 3% for luminosities up to 6.5 × 1033 cm–2s–1. Further prescale sets have been created for 7 and 8 × 1033 cm–2s–1 luminosities. The L1 DPG is evaluating the performance of the Trigger for upcoming conferences and publication. Progress on the Trigger upgrade was reviewed during the May Upgrade Week. We are investigating scenarios for stagin...

  15. TRIGGER

    CERN Multimedia

    R. Arcidiacono

    2013-01-01

      In 2013 the Trigger Studies Group (TSG) has been restructured in three sub-groups: STEAM, for the development of new HLT menus and monitoring their performance; STORM, for the development of HLT tools, code and actual configurations; and FOG, responsible for the online operations of the High Level Trigger. The Strategy for Trigger Evolution And Monitoring (STEAM) group is responsible for Trigger Menu development, path timing, trigger performance studies coordination, HLT offline DQM as well as HLT release, menu and conditions validation – in collaboration and with the technical support of the PdmV group. Since the end of proton-proton data taking, the group has started preparing for 2015 data taking, with collisions at 13 TeV and 25 ns bunch spacing. The reliability of the extrapolation to higher energy is being evaluated comparing the trigger rates on 7 and 8 TeV Monte Carlo samples with the data taken in the past two years. The effect of 25 ns bunch spacing is being studied on the d...

  16. [Cardiac arrhythmias: Diagnosis and management].

    Science.gov (United States)

    Waldmann, V; Marijon, E

    2016-09-01

    Cardiac arrhythmias, with, on top of the list, atrial fibrillation, are frequent conditions and any physician might have to get involved at any stage of patient care (from diagnosis to treatment), without always having the opportunity to immediately refer to the cardiologist. The aim of this review is to present a summary of pathophysiology, clinical and electrocardiographic presentations, as well as diagnostic and therapeutic strategies for the main cardiac arrhythmias. Supra-ventricular tachycardias (atrial fibrillation and flutter, atrioventricular reciprocating tachycardias) and ventricular tachycardias will be consecutively presented and discussed. Copyright © 2016 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  17. TRIGGER

    CERN Multimedia

    W. Smith

    2011-01-01

    Level-1 Trigger Hardware and Software Overall the L1 trigger hardware has been running very smoothly during the last months of proton running. Modifications for the heavy-ion run have been made where necessary. The maximal design rate of 100 kHz can be sustained without problems. All L1 latencies have been rechecked. The recently installed Forward Scintillating Counters (FSC) are being used in the heavy ion run. The ZDC scintillators have been dismantled, but the calorimeter itself remains. We now send the L1 accept signal and other control signals to TOTEM. Trigger cables from TOTEM to CMS will be installed during the Christmas shutdown, so that the TOTEM data can be fully integrated within the CMS readout. New beam gas triggers have been developed, since the BSC-based trigger is no longer usable at high luminosities. In particular, a special BPTX signal is used after a quiet period with no collisions. There is an ongoing campaign to provide enough spare modules for the different subsystems. For example...

  18. TRIGGER

    CERN Multimedia

    J. Alimena

    2013-01-01

    Trigger Strategy Group The Strategy for Trigger Evolution And Monitoring (STEAM) group is responsible for the development of future High-Level Trigger menus, as well as of its DQM and validation, in collaboration and with the technical support of the PdmV group. Taking into account the beam energy and luminosity expected in 2015, a rough estimate of the trigger rates indicates a factor four increase with respect to 2012 conditions. Assuming that a factor two can be tolerated thanks to the increase in offline storage and processing capabilities, a toy menu has been developed using the new OpenHLT workflow to estimate the transverse energy/momentum thresholds that would halve the current trigger rates. The CPU time needed to run the HLT has been compared between data taken with 25 ns and 50 ns bunch spacing, for equivalent pile-up: no significant difference was observed on the global time per event distribution at the only available data point, corresponding to a pile-up of about 10 interactions. Using th...

  19. TRIGGER

    CERN Multimedia

    by Wesley Smith

    2011-01-01

    Level-1 Trigger Hardware and Software After the winter shutdown minor hardware problems in several subsystems appeared and were corrected. A reassessment of the overall latency has been made. In the TTC system shorter cables between TTCci and TTCex have been installed, which saved one bunch crossing, but which may have required an adjustment of the RPC timing. In order to tackle Pixel out-of-syncs without influencing other subsystems, a special hardware/firmware re-sync protocol has been introduced in the Global Trigger. The link between the Global Calorimeter Trigger and the Global Trigger with the new optical Global Trigger Interface and optical receiver daughterboards has been successfully tested in the Electronics Integration Centre in building 904. New firmware in the GCT now allows a setting to remove the HF towers from energy sums. The HF sleeves have been replaced, which should lead to reduced rates of anomalous signals, which may allow their inclusion after this is validated. For ECAL, improvements i...

  20. The antiarrhythmic peptide analog ZP123 prevents atrial conduction slowing during metabolic stress

    DEFF Research Database (Denmark)

    Haugan, Ketil; Olsen, Kristine Boisen; Hartvig, Line

    2005-01-01

    OBJECTIVE: As atrial conduction slowing is important in the pathogenesis of atrial reentry arrhythmias, a drug that increases atrial conduction or prevents atrial conduction slowing could serve to prevent atrial reentry arrhythmias. In this study, we investigated whether the novel stable antiarrh......OBJECTIVE: As atrial conduction slowing is important in the pathogenesis of atrial reentry arrhythmias, a drug that increases atrial conduction or prevents atrial conduction slowing could serve to prevent atrial reentry arrhythmias. In this study, we investigated whether the novel stable...... antiarrhythmic peptide analog, ZP123, was able to prevent atrial conduction slowing. METHODS: We examined the effect of ZP123 on metabolic stress-induced changes in conduction velocity (CV) and on dynamic CV restitution in isolated left atria from male Sprague-Dawley rats. We performed binding of ZP123...

  1. TRIGGER

    CERN Multimedia

    W. Smith

    Level-1 Trigger Hardware The CERN group is working on the TTC system. Seven out of nine sub-detector TTC VME crates with all fibers cabled are installed in USC55. 17 Local Trigger Controller (LTC) boards have been received from production and are in the process of being tested. The RF2TTC module replacing the TTCmi machine interface has been delivered and will replace the TTCci module used to mimic the LHC clock. 11 out of 12 crates housing the barrel ECAL off-detector electronics have been installed in USC55 after commissioning at the Electronics Integration Centre in building 904. The cabling to the Regional Calorimeter Trigger (RCT) is terminated. The Lisbon group has completed the Synchronization and Link mezzanine board (SLB) production. The Palaiseau group has fully tested and installed 33 out of 40 Trigger Concentrator Cards (TCC). The seven remaining boards are being remade. The barrel TCC boards have been tested at the H4 test beam, and good agreement with emulator predictions were found. The cons...

  2. Effectiveness of amiodarone in resistant arrhythmias1

    OpenAIRE

    Hollman, Arthur; Holt, Phyllis M

    1980-01-01

    Amiodarone is used in the treatment of previously drug-resistant supraventricular and ventricular arrhythmias. We report our experience with amiodarone in 8 patients. Five patients had paroxysmal atrial flutter, one had paroxysmal atrial fibrillation, one had supraventricular tachycardia, and one ventricular tachycardia. Considerable improvement, both objectively and subjectively, was observed in all patients. Side effects were as follows: all patients had corneal microdeposits, one developed...

  3. Update on arrhythmias and cardiac pacing 2013.

    Science.gov (United States)

    Almendral, Jesús; Pombo, Marta; Martínez-Alday, Jesús; González-Rebollo, José M; Rodríguez-Font, Enrique; Martínez-Ferrer, José; Castellanos, Eduardo; García-Fernández, F Javier; Ruiz-Mateas, Francisco

    2014-04-01

    This report discusses a selection of the most relevant articles on cardiac arrhythmias and pacing published in 2013. The first section discusses arrhythmias, classified as regular paroxysmal supraventricular tachyarrhythmias, atrial fibrillation, and ventricular arrhythmias, together with their treatment by means of an implantable cardioverter defibrillator. The next section reviews cardiac pacing, subdivided into resynchronization therapy, remote monitoring of implantable devices, and pacemakers. The final section discusses syncope. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

  4. Arrhythmias are not to blame for all cardiac syncope patients: left atrial myxoma causing syncope in a middle-aged man.

    Science.gov (United States)

    Rajani, Ali Raza; Muaz, Reem Naif; Govindaswamy, Pushpa Rani; Mian, Muhammad Hamid

    2015-04-15

    A 47-year-old man presented with a history of syncope that lasted for 3 min and was not accompanied by jerky movement of limbs or incontinence. After regaining consciousness, he felt generalised weakness. There was no history of chest pain or palpitation. ECG showed normal sinus rhythm. All blood investigations were normal. Transthoracic echocardiography showed a large multilobulated echo dense mass in the left atrium. The mass was prolapsing through the mitral valve during diastole. Transoesophageal echocardiography verified these findings and also showed the stalk of the mass attached to the interatrial septum near the fossa ovalis. The mass was highly suggestive of myxoma. The patient underwent surgical resection of the mass and histopathology confirmed the diagnosis of left atrial myxoma. 2015 BMJ Publishing Group Ltd.

  5. Arrhythmias in Adults with Congenital Heart Disease: What Are Risk Factors for Specific Arrhythmias?

    Science.gov (United States)

    Loomba, Rohit S; Buelow, Matthew W; Aggarwal, Saurabh; Arora, Rohit R; Kovach, Joshua; Ginde, Salil

    2017-04-01

    An increasing number of patients with congenital heart disease are now surviving into adulthood. This has also led to the emergence of complications from the underlying congenital heart disease, related surgical interventions, and associated combordities. While the prevalence of particular arrhythmias with specific congenital heart disease has been previously described, a detailed analysis of all lesions and a large number of comorbidities has not been previously published. Admissions with congenital heart disease were identified in the National Inpatient Sample. Associated comorbidities were also identified for these patients. Univariate analysis was done to compare those risk factors associated with specific arrhythmias in the setting of congenital heart disease. Next, regression analysis was done to identify what patient characteristics and comorbidities were associated with increased risk of specific arrhythmias. A total of 52,725,227 admissions were included in the analysis. Of these, 109,168 (0.21%) had congenital heart disease. Of those with congenital heart disease, 27,088 (25%) had an arrhythmia at some point. The most common arrhythmia in those with congenital heart disease was atrial fibrillation, which was noted in 86% of those with arrhythmia followed by atrial flutter which was noted in 20% of those with congenital heart disease. The largest burden of arrhythmia was found to be in those with tricuspid atresia with a 51% prevalence of arrhythmia in this group followed by Ebstein anomaly which had an arrhythmia prevalence of 39%. Increasing age, male gender, double outlet right ventricle, atrioventricular septal defect, heart failure, obstructive sleep apnea, transposition of the great arteries, congenitally corrected transposition, and tetralogy of Fallot were frequently noted to be independent risk factors of specific arrhythmias. Approximately, 25% of adult admissions with congenital heart disease are associated with arrhythmia. The burden of

  6. A randomized comparison of amiodarone and class IC antiarrhythmic drugs to treat atrial fibrillation in patients paced for sinus node disease: the Prevention Investigation and Treatment: A Group for Observation and Research on Atrial arrhythmias (PITAGORA) trial.

    Science.gov (United States)

    Gulizia, Michele; Mangiameli, Salvatore; Orazi, Serafino; Chiarandà, Giacomo; Piccione, Guglielmo; Di Giovanni, Nicolò; Colletti, Andrea; Pensabene, Orazio; Lisi, Francesco; Vasquez, Ludovico; Grammatico, Andrea; Boriani, Giuseppe

    2008-01-01

    Rhythm control is an important goal in the treatment of recurrent atrial tachyarrhythmias (AT). The PITAGORA study was a randomized trial in patients paced for sinus node disease (SND), designed to test the noninferiority of class IC antiarrhythmic drugs (AADs) to amiodarone in terms of a primary end point composed of death, permanent AT, cardiovascular hospitalization, atrial cardioversion, or AAD change. Randomization was stratified to assign 2 patients to amiodarone and 2 patients to class IC AADs: propafenone or flecainide. One hundred seventy-six patients (46% men, 72 +/- 8 years) were enrolled. Device diagnostics continuously monitored AT recurrences and duration. In a mean follow-up of 20 +/- 9 months, the primary end point occurred in 23 (30.7%) of 75 class IC patients and in 28 (40.0%) of 70 amiodarone patients. The absolute difference in the end point incidence (-9.3%; 95% CI between 3.7% and -22.3%) confirmed the noninferiority of class IC to amiodarone (P = .007). Kaplan-Meier 1-year freedom from AT episodes >10 minutes, 1 day, and 7 days was 40%, 73%, and 91% for amiodarone and 28%, 78%, and 86% for class IC AADs (P = nonsignificant). In patients paced for SND and suffering from AT, class IC AADs proved not to be inferior to amiodarone in terms of the primary composite end point described or end points which were differently composed of mortality, efficacy, or AAD side effects. The AADs studied also showed similar results in terms of symptoms, quality of life, and freedom from AT recurrences.

  7. Magnetism and cardiac arrhythmias.

    Science.gov (United States)

    Scherlag, Benjamin J; Yamanashi, William S; Hou, Yuemei; Jacobson, Jerry I; Jackman, Warren M; Lazzara, Ralph

    2004-01-01

    Low-level electromagnetic fields (EMFs) have been used to treat various neurologic disorders. In the present study, we applied micro Gauss (microG) levels of EMFs either to the vagosympathetic nerve trunks, dissected in the neck, or across the chest in anesthetized dogs. Based on theoretical and empiric grounds, we compared EMFs (2.87 microG at 0.043 Hz) delivered to the vagosympathetic trunks in an experimental set (n = 5) with a sham control group (n = 6). Over a period of 2 to 3 hours, heart rate decreased after an initial 5-minute EMF exposure. The maximal heart rate changes in the experimental versus control groups was 29% versus 12% (P = 0.03). The voltage applied to the autonomic nerves required to induce atrioventricular (AV) conduction block decreased by 60% in the experimental group versus a 5% increase in the control group (P = 0.005). This effect also lasted 2 to 3 hours. Another EMF setting (amplitude 0.34 microG, frequency 2 kHz) applied for 5 minutes to the vagosympathetic trunks was associated with a significant increase in the occurrence of atrial premature depolarizations (APDs), atrial tachycardia (AT), and atrial fibrillation (AF) in response to autonomic nerve stimulation compared with control states before EMF exposure. No atrial arrhythmias could be induced after propranolol and atropine, even at the highest voltage used to stimulate the autonomic nervous input to the heart (n = 11). Only 2 dogs showed no response to this EMF application. In 3 dogs in whom atrial pacing (cycle length = 250 ms) and autonomic nerve stimulation induced AF, an EMF (2.87 microG at 0.043 Hz) delivered for 35 minutes across the chest suppressed AF for up to 3 to 4 hours, after which the same protocol again induced AF. We conclude that in these preliminary experiments, specific low-level EMFs alter heart rate, AV conduction, and heart rhythm. These effects were mediated through the autonomic nervous system inputs to the heart based on adjunctive effect of autonomic

  8. Cardiac arrhythmias during exercise testing in healthy men.

    Science.gov (United States)

    Beard, E. F.; Owen, C. A.

    1973-01-01

    Clinically healthy male executives who participate in a long-term physical conditioning program have demonstrated cardiac arrhythmia during and after periodic ergometric testing at submaximal and maximal levels. In 1,385 tests on 248 subjects, it was found that 34% of subjects demonstrated an arrhythmia at some time and 13% of subjects developed arrhythmia on more than one test. Premature systoles of ventricular origin were most common, but premature systoles of atrial origin, premature systoles of junctional origin, paroxysmal atrial tachycardia, atrioventricular block, wandering pacemaker, and pre-excitation were also seen. Careful post-test monitoring and pulse rate regulated training sessions are suggested for such programs.

  9. Electrocardiographic abnormalities and cardiac arrhythmias in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Goudis, Christos A; Konstantinidis, Athanasios K; Ntalas, Ioannis V; Korantzopoulos, Panagiotis

    2015-11-15

    Chronic obstructive pulmonary disease (COPD) is independently associated with an increased burden of cardiovascular disease. Besides coronary artery disease (CAD) and congestive heart failure (CHF), specific electrocardiographic (ECG) abnormalities and cardiac arrhythmias seem to have a significant impact on cardiovascular prognosis of COPD patients. Disturbances of heart rhythm include premature atrial contractions (PACs), premature ventricular contractions (PVCs), atrial fibrillation (AF), atrial flutter (AFL), multifocal atrial tachycardia (MAT), and ventricular tachycardia (VT). Of note, the identification of ECG abnormalities and the evaluation of the arrhythmic risk may have significant implications in the management and outcome of patients with COPD. This article provides a concise overview of the available data regarding ECG abnormalities and arrhythmias in these patients, including an elaborated description of the underlying arrhythmogenic mechanisms. The clinical impact and prognostic significance of ECG abnormalities and arrhythmias in COPD as well as the appropriate antiarrhythmic therapy and interventions in this setting are also discussed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Epidemiology of Arrhythmias in Children

    Directory of Open Access Journals (Sweden)

    R Prem Sekar

    2008-05-01

    Full Text Available Unlike the adult population, arrhythmias occur less commonly in childhood. Only 5% of the emergency hospital admissions in the paediatric population is attributed to symptomatic arrhythmias. Majority of these tend to be accessory pathway mediated supraventricular tachyarrhythmias such as Wolff-Parkinson-White (WPW syndrome, permanent junctional reciprocating tachycardia (PJRT and Mahaim tachycardia. The non accessory pathway mediated supraventricular tachyarrhythmias commonly seen in children are junctional ectopic tachycardia (JET and automatic ectopic atrial tachycardia (AET and occur mostly in the post operative period after intracardiac repair for a structural heart defect. Ventricular tachycardia (VT although uncommon, occurs in the paediatric age group in association with hypertrophic cardiomyopathy (HCM, long QT syndrome (LQTS and Brugada syndrome. Occasionally, VT can also present symptomatically as incessant idiopathic infant ventricular tachycardia, right ventricular outflow tract tachycardia, benign VT, catecholaminic VT, idiopathic left ventricular tachycardia and in post cardiac surgical patients.

  11. Gene Therapy in Cardiac Arrhythmias

    Directory of Open Access Journals (Sweden)

    Praveen S.V

    2006-04-01

    Full Text Available Gene therapy has progressed from a dream to a bedside reality in quite a few human diseases. From its first application in adenosine deaminase deficiency, through the years, its application has evolved to vascular angiogenesis and cardiac arrhythmias. Gene based biological pacemakers using viral vectors or mesenchymal cells tested in animal models hold much promise. Induction of pacemaker activity within the left bundle branch can provide stable heart rates. Genetic modification of the AV node mimicking beta blockade can be therapeutic in the management of atrial fibrillation. G protein overexpression to modify the AV node also is experimental. Modification and expression of potassium channel genes altering the delayed rectifier potassium currents may permit better management of congenital long QT syndromes. Arrhythmias in a failing heart are due to abnormal calcium cycling. Potential targets for genetic modulation include the sarcoplasmic reticulum calcium pump, calsequestrin and sodium calcium exchanger.Lastly the ethical concerns need to be addressed.

  12. Atrial Ectopics Precipitating Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Johnson Francis

    2015-04-01

    Full Text Available Holter monitor tracing showing blocked atrial ectopics and atrial ectopic precipitating atrial fibrillation is being demonstrated. Initially it was coarse atrial fibrillation, which rapidly degenerated into fine atrial fibrillation.

  13. [Atrial defibrillator].

    Science.gov (United States)

    Jung, W; Lüderitz, B

    2000-01-01

    Atrial fibrillation (AF) is a frequent and costly health care problem representing the most common arrhythmia resulting in hospital admission. Total mortality and cardiovascular mortality are significantly increased in patients with AF compared to controls. In addition to symptoms of palpitations, patients with AF have an increased risk of stroke and may also develop decreased exercise tolerance and left ventricular dysfunction. All of these problems may be reversed with restoration and maintenance of sinus rhythm. External electrical cardioversion has been a remarkably effective and safe method for termination of this arrhythmia. Originally described by Lown et al. in 1963, it has been a well accepted mode of acute therapy. However, this technique requires general anesthesia or heavy sedation. Internal atrial defibrillation has been evaluated as an alternative approach to the external technique for over 2 decades. Recent studies have shown that low-energy internal atrial defibrillation using biphasic shocks is an effective and safe means in restoring sinus rhythm in patients with AF and should be considered especially in patients in whom external cardioversion attempts have failed. Implantable Atrial Defibrillator: Recently, a stand alone IAD, the Metrix System (models 3000 and 3020), has entered clinical investigation. Atrial defibrillation is accomplished by a shock delivered between electrodes in the right atrium and the coronary sinus. The right atrium lead has an active fixation in the right atrium. The coronary sinus lead has a natural spiral configuration for retention in the coronary sinus, and can be straightened with a stylet. Both leads are 7 French in diameter and the defibrillation coils are each 6 cm in length. The electrodes may be placed using separate leads, or very soon by using a single bipolar lead. A separate bipolar right ventricular lead is used for R wave synchronization and post shock pacing. The Metrix defibrillator can be used to induce

  14. Acute cardiac arrhythmias following surgery for congenital heart disease: mechanisms, diagnostic tools, and management.

    Science.gov (United States)

    Payne, Linda; Zeigler, Vicki L; Gillette, Paul C

    2011-06-01

    This article focuses on the management of those cardiac arrhythmias most commonly seen in the immediate postoperative period. They include ventricular tachycardia, ventricular fibrillation, atrial flutter, junctional ectopic tachycardia, bradycardia, and atrioventricular block. The mechanisms of cardiac arrhythmias are reviewed followed by a brief overview of the predominant acute arrhythmias, tools used for the diagnostic evaluation of these arrhythmias, management strategies, and, finally, nursing considerations. Copyright © 2011. Published by Elsevier Inc.

  15. Arrhythmias in type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Gaurav Agarwal

    2017-01-01

    Full Text Available Chronic hyperglycaemia of Type 2 diabetes mellitus causes long term damage to heart resulting in coronary artery disease (CAD, myocardial infarction (MI, congestive heart failure (CHF, and sudden death from arrhythmias. AIMS: To study the prevalence of different types of arrhythmias in T2DM, particularly in association with Cardiac Autonomic Neuropathy (CAN. METHODS: A cross-sectional study including 100 patients of Type 2 Diabetes Mellitus (T2DM presenting with cardiac arrhythmias, was done at our hospital over 2 years. Detailed history along with physical examination and tests for CAN were done. Routine investigations along with echocardiography, stress test, Holter monitoring were done. RESULTS: Sinus Tachycardia (ST was the commonest arrhythmia, found in 32% of patients. 20% had Complete Heart Block (CHB, 15% had Sinus Bradycardia (SB, and 15% had Atrial Fibrillation (AF. Ventricular Premature Complex (VPC was found in 10% and 3% had Atrial Premature Complex (APC. 3% had first degree AV block, whereas 1% had Paroxysmal Supra Ventricular Tachycardia (PSVT, and another 1% had Ventricular Tachycardia (VT. Poorly controlled diabetes and co-morbidities was associated with higher incidence of arrhythmias. 62% of patients had prolonged QTc, majority of which had CAN. Most of the patients responded to standard therapy.

  16. Long-Term Exposure to Traffic-Related Air Pollution and Risk of Incident Atrial Fibrillation

    DEFF Research Database (Denmark)

    Monrad, Maria; Sajadieh, Ahmad; Christensen, Jeppe Schultz

    2017-01-01

    BACKGROUND: Atrial fibrillation is the most common sustained arrhythmia and associated with cardiovascular morbidity and mortality. The few studies conducted on short-term effects of air pollution on episodes of atrial fibrillation indicates a positive association, though not consistently...

  17. Prospectively ECG-Triggered Sequential Dual-Source Coronary CT Angiography in Patients with Atrial Fibrillation: Influence of Heart Rate on Image Quality and Evaluation of Diagnostic Accuracy.

    Directory of Open Access Journals (Sweden)

    Lin Yang

    Full Text Available To evaluate the effects of mean heart rate (HR and heart rate variation (HRV on image quality and diagnostic accuracy of prospectively ECG-triggered sequential dual-source coronary CT angiography (CCTA in patients with atrial fibrillation (AF.Eighty-five patients (49 women, 36 men; mean age 62. 1 ± 9.5 years with persistent AF underwent prospectively ECG-triggered sequential second-generation dual-source CCTA. Tube current and voltage were adjusted according to body mass index (BMI and iterative reconstruction was used. Image quality of coronary segments (four-point scale and presence of significant stenosis (>50% were evaluated. Diagnostic accuracy was analyzed in 30 of the 85 patients who underwent additional invasive coronary angiography (ICA.Only 8 of 1102 (0.7% segments demonstrated poor image quality. No significant impact on image quality was found for mean HR (94.9 ± 21.8 bpm; r=0.034, p=0.758; F=0.413, p=0.663 or HRV (67.5 ± 22.8 bpm; r=0.097, p=0.377; F=0.111, p=0.895. On per-segment analysis, sensitivity, specificity, positive predictive value (PPV, and negative predictive value (NPV were 89.7% (26/29, 99.4% (355/357, 92.9% (26/28, and 99.2% (355/358, respectively, with excellent correlation (kappa=0.91 with ICA. Mean effective dose was 3.3 ± 1.0 mSv.Prospectively ECG-triggered sequential dual-source CCTA provides diagnostic image quality and good diagnostic accuracy for detection of coronary stenosis in AF patients without significant influence by HR or HRV.

  18. Inhibitors of arachidonate-regulated calcium channel signaling suppress triggered activity induced by the late sodium current.

    Science.gov (United States)

    Wolkowicz, Paul; Umeda, Patrick K; Sharifov, Oleg F; White, C Roger; Huang, Jian; Mahtani, Harry; Urthaler, Ferdinand

    2014-02-05

    Disturbances in myocyte calcium homeostasis are hypothesized to be one cause for cardiac arrhythmia. The full development of this hypothesis requires (i) the identification of all sources of arrhythmogenic calcium and (ii) an understanding of the mechanism(s) through which calcium initiates arrhythmia. To these ends we superfused rat left atria with the late sodium current activator type II Anemonia sulcata toxin (ATXII). This toxin prolonged atrial action potentials, induced early afterdepolarization, and provoked triggered activity. The calmodulin-dependent protein kinase II (CaMKII) inhibitor KN-93 (N-[2-[[[3-(4-chlorophenyl)-2-propenyl]methylamino]methyl]phenyl]-N-(2-hydroxyethyl)-4-methoxybenzenesulphon-amide) suppressed ATXII triggered activity but its inactive congener KN-92 (2-[N-(4-methoxy benzenesulfonyl)]amino-N-(4-chlorocinnamyl)-N-methylbenzylamine) did not. Neither drug affected normal atrial contractility. Calcium entry via L-type channels or calcium leakage from sarcoplasmic reticulum stores are not critical for this type of ectopy as neither verapamil ((RS)-2-(3,4-dimethoxyphenyl)-5-{[2-(3,4-dimethoxyphenyl)ethyl]-(methyl)amino}-2-prop-2-ylpentanenitrile) nor ryanodine affected ATXII triggered activity. By contrast, inhibitors of the voltage independent arachidonate-regulated calcium (ARC) channel and the store-operated calcium channel specifically suppressed ATXII triggered activity without normalizing action potentials or affecting atrial contractility. Inhibitors of cytosolic calcium-dependent phospholipase A2 also suppressed triggered activity suggesting that this lipase, which generates free arachidonate, plays a key role in ATXII ectopy. Thus, increased left atrial late sodium current appears to activate atrial Orai-linked ARC and store operated calcium channels, and these voltage-independent channels may be unexpected sources for the arrhythmogenic calcium that underlies triggered activity. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. New risk factors for atrial fibrillation : causes of 'not-so-lone atrial fibrillation'

    NARCIS (Netherlands)

    Schoonderwoerd, Bas A.; Smit, Marcelle D.; Pen, Lucas; Van Gelder, Isabelle C.

    Atrial fibrillation (AF) is a prevalent arrhythmia in patients with cardiovascular disease. The classical risk factors for developing AF include hypertension, valvular disease, (ischaemic) cardiomyopathy, diabetes mellitus, and thyroid disease. In some patients with AF, no underlying

  20. Idiopathic giant right atrial aneurysm

    Science.gov (United States)

    Uppu, Santosh C; Sachdeva, Ritu; Imamura, Michiaki

    2013-01-01

    A 2-year-old boy with an incidental finding of massive cardiomegaly on a chest X-ray was diagnosed with a giant right atrial aneurysm upon further investigation with echocardiography. The patient underwent successful surgical reduction of the right atrium and closure of the patent foramen ovale to prevent thromboembolic complications and to lower the risk of atrial arrhythmias. The resected atrium had paper-thin walls and pathological features of interstitial fibrosis with endocardial thickening. PMID:23626440

  1. Increased susceptibility to atrial fibrillation secondary to atrial fibrosis in transgenic goats expressing transforming growth factor - B1

    Science.gov (United States)

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in people with significant morbidity and mortality. There is a strong association between atrial fibrosis and AF. Transforming growth factor B1 (TGF-B1) is an essential mediator of atrial fibrosis in animal models and human pat...

  2. Cardiac arrhythmias during or after epileptic seizures.

    Science.gov (United States)

    van der Lende, Marije; Surges, Rainer; Sander, Josemir W; Thijs, Roland D

    2016-01-01

    Seizure-related cardiac arrhythmias are frequently reported and have been implicated as potential pathomechanisms of Sudden Unexpected Death in Epilepsy (SUDEP). We attempted to identify clinical profiles associated with various (post)ictal cardiac arrhythmias. We conducted a systematic search from the first date available to July 2013 on the combination of two terms: 'cardiac arrhythmias' and 'epilepsy'. The databases searched were PubMed, Embase (OVID version), Web of Science and COCHRANE Library. We attempted to identify all case reports and case series. We identified seven distinct patterns of (post)ictal cardiac arrhythmias: ictal asystole (103 cases), postictal asystole (13 cases), ictal bradycardia (25 cases), ictal atrioventricular (AV)-conduction block (11 cases), postictal AV-conduction block (2 cases), (post)ictal atrial flutter/atrial fibrillation (14 cases) and postictal ventricular fibrillation (3 cases). Ictal asystole had a mean prevalence of 0.318% (95% CI 0.316% to 0.320%) in people with refractory epilepsy who underwent video-EEG monitoring. Ictal asystole, bradycardia and AV-conduction block were self-limiting in all but one of the cases and seen during focal dyscognitive seizures. Seizure onset was mostly temporal (91%) without consistent lateralisation. Postictal arrhythmias were mostly found following convulsive seizures and often associated with (near) SUDEP. The contrasting clinical profiles of ictal and postictal arrhythmias suggest different pathomechanisms. Postictal rather than ictal arrhythmias seem of greater importance to the pathophysiology of SUDEP. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  3. Atrial Fibrillation after Robotic Cardiac Surgery

    OpenAIRE

    LEONARDO CANALE; STEPHANIE MICK; RAVI NAIR; TOMISLAV MIHALJEVIC; JOHANNES BONATTI

    2014-01-01

    Atrial fibrillation is a common arrhythmia after conventional open heart surgery. A minimally invasive robotic approach has the potential to lower its occurrence. We sought to review the literature on the incidence of post operative atrial fibrillation in robotic heart surgery and compare it to the incidence in conventional cardiac surgery. The types of operation investigated were: coronary artery bypass surgery, mitral valve repair, atrial septal defect closure and myxoma excision. Operation...

  4. Cardiac arrhythmia classification using autoregressive modeling

    Directory of Open Access Journals (Sweden)

    Srinivasan Narayanan

    2002-11-01

    Full Text Available Abstract Background Computer-assisted arrhythmia recognition is critical for the management of cardiac disorders. Various techniques have been utilized to classify arrhythmias. Generally, these techniques classify two or three arrhythmias or have significantly large processing times. A simpler autoregressive modeling (AR technique is proposed to classify normal sinus rhythm (NSR and various cardiac arrhythmias including atrial premature contraction (APC, premature ventricular contraction (PVC, superventricular tachycardia (SVT, ventricular tachycardia (VT and ventricular fibrillation (VF. Methods AR Modeling was performed on ECG data from normal sinus rhythm as well as various arrhythmias. The AR coefficients were computed using Burg's algorithm. The AR coefficients were classified using a generalized linear model (GLM based algorithm in various stages. Results AR modeling results showed that an order of four was sufficient for modeling the ECG signals. The accuracy of detecting NSR, APC, PVC, SVT, VT and VF were 93.2% to 100% using the GLM based classification algorithm. Conclusion The results show that AR modeling is useful for the classification of cardiac arrhythmias, with reasonably high accuracies. Further validation of the proposed technique will yield acceptable results for clinical implementation.

  5. Optimal Analysis of Left Atrial Strain by Speckle Tracking Echocardiography: P-wave versus R-wave Trigger.

    Science.gov (United States)

    Hayashi, Shuji; Yamada, Hirotsugu; Bando, Mika; Saijo, Yoshihito; Nishio, Susumu; Hirata, Yukina; Klein, Allan L; Sata, Masataka

    2015-08-01

    Left atrial (LA) strain analysis using speckle tracking echocardiography is useful for assessing LA function. However, there is no established procedure for this method. Most investigators have determined the electrocardiographic R-wave peak as the starting point for LA strain analysis. To test our hypothesis that P-wave onset should be used as the starting point, we measured LA strain using 2 different starting points and compared the strain values with the corresponding LA volume indices obtained by three-dimensional (3D) echocardiography. We enrolled 78 subjects (61 ± 17 years, 25 males) with and without various cardiac diseases in this study and assessed global longitudinal LA strain by two-dimensional speckle tracking strain echocardiography using EchoPac software. We used either R-wave peak or P-wave onset as the starting point for determining LA strains during the reservoir (Rres, Pres), conduit (Rcon, Pcon), and booster pump (Rpump, Ppump) phases. We determined the maximum, minimum, and preatrial contraction LA volumes, and calculated the LA total, passive, and active emptying fractions using 3D echocardiography. The correlation between Pres and LA total emptying fraction was better than the correlation between Rres and LA total emptying fraction (r = 0.458 vs. 0.308, P = 0.026). Pcon and Ppump exhibited better correlation with the corresponding 3D echocardiographic parameters than Rcon (r = 0.560 vs. 0.479, P = 0.133) and Rpump (r = 0.577 vs. 0.345, P = 0.003), respectively. LA strain in any phase should be analyzed using P-wave onset as the starting point rather than R-wave peak. © 2014, Wiley Periodicals, Inc.

  6. Epidemiology of Arrhythmias and Conduction Disorders in Older Adults

    Science.gov (United States)

    Chow, Grant V.; Marine, Joseph E.; Fleg, Jerome L.

    2012-01-01

    Normal aging is associated with a multitude of changes in the cardiovascular system, including decreased compliance of blood vessels, mild concentric left ventricular hypertrophy, an increased contribution of atrial contraction to left ventricular filling, and a higher incidence of many cardiac arrhythmias, both bradyarrhythmias and tachyarrhythmias. Conduction disorders also become more common with age, and may either be asymptomatic, or cause hemodynamic changes requiring treatment. The epidemiology of common arrhythmias and conduction disorders in the elderly is reviewed. PMID:23101570

  7. Abnormal atrial activation in young patients with lone atrial fibrillation

    DEFF Research Database (Denmark)

    Holmqvist, Fredrik; Olesen, Morten S; Tveit, Arnljot

    2011-01-01

    -wave morphology distribution was seen between patients with early-onset, lone paroxysmal AF and age- and gender-matched healthy control subjects. This finding indicates that alterations in atrial electrophysiology are common in the early stage of the arrhythmia, and since it occurs in young patients without co...

  8. Arrhythmias in the intensive care patient.

    Science.gov (United States)

    Trappe, Hans-Joachim; Brandts, Bodo; Weismueller, Peter

    2003-10-01

    Atrial fibrillation, atrial flutter, AV-nodal reentry tachycardia with rapid ventricular response, atrial ectopic tachycardia, and preexcitation syndromes combined with atrial fibrillation or ventricular tachyarrhythmias are typical arrhythmias in intensive care patients. Most frequently, the diagnosis of the underlying arrhythmia is possible from the physical examination, the response to maneuvers or drugs, and the 12-lead surface electrocardiogram. In all patients with unstable hemodynamics, immediate DC-cardioversion is indicated. Conversion of atrial fibrillation to sinus rhythm is possible using antiarrhythmic drugs. Amiodarone has a conversion rate in atrial fibrillation of up to 80%. However, caution in the use of short-term administration of intravenous amiodarone in critically ill patients with recent-onset atrial fibrillation is absolutely necessary, and the duration of therapy should not exceed 24 to 48 hours. Ibutilide represents a relatively new class III antiarrhythmic agent that has been reported to have conversion rates of 50% to 70%; it seems that ibutilide is even successful when intravenous amiodarone failed to convert atrial fibrillation. Newer studies compared the outcome of patients with atrial fibrillation and rhythm- or rate-control. Data from these studies (AFFIRM, RACE) clearly showed that rhythm control is not superior to rate control for the prevention of death and morbidity from cardiovascular causes. Therefore, rate-control may be an appropriate therapy in patients with recurrent atrial fibrillation after DC-cardioversion. Acute therapy of atrial flutter in intensive care patients depends on the clinical presentation. Atrial flutter can most often be successfully cardioverted to sinus rhythm with energies less than 50 joules. Ibutilide trials showed efficacy rates of 38-76% for conversion of atrial flutter to sinus rhythm compared with conversion rates of 5-13% when intravenous flecainide, propafenone, or verapamil was administered. In

  9. Very early-onset lone atrial fibrillation patients have a high prevalence of rare variants in genes previously associated with atrial fibrillation

    DEFF Research Database (Denmark)

    Olesen, Morten S; Andreasen, Laura; Jabbari, Javad

    2014-01-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia. Currently, 14 genes important for ion channel function, intercellular signalling, and homeostatic control have been associated with AF.......Atrial fibrillation (AF) is the most common cardiac arrhythmia. Currently, 14 genes important for ion channel function, intercellular signalling, and homeostatic control have been associated with AF....

  10. Atrial defibrillation threshold in humans minutes after atrial fibrillation induction; "A stitch in time saves nine".

    Science.gov (United States)

    Vardas, P E; Manios, E G; Kanoupakis, E M; Dermitzaki, D N; Mavrakis, H E; Kallergis, E M

    2001-09-01

    To assess the effects of atrial fibrillation duration on the defibrillation threshold in atrial fibrillation patients seconds or minutes after initiation of the arrhythmia. Nineteen patients with recurrent symptomatic atrial fibrillation were evaluated. After programmed induction of atrial fibrillation, the defibrillation threshold was assessed after two sequential periods of arrhythmia in the same patient: an "ultrashort" period of 30 s duration and a "short" period, which lasted 10 min. After the specified period, internal cardioversion was attempted using a balloon-guided catheter that allows the delivery of biphasic shocks between one electrode array placed in the left pulmonary artery and a proximal electrode array on the lateral right atrial wall. The defibrillation threshold was assessed with energy steps of 0.5 J with a starting level of 0.5 J. Mean time from induction to successful defibrillation was 92+/-30 s after the "ultrashort" period of atrial fibrillation and 910+/-86 s after the short period. The defibrillation threshold was significantly greater after 10 min of atrial fibrillation than after 30 s of arrhythmia (2.32+/-0.61 J vs 1.31+/-0.66 J, Pdefibrillation threshold. Prolongation of atrial fibrillation over minutes in patients with paroxysmal arrhythmia increases the energy requirements for successful defibrillation. Copyright 2001 The European Society of Cardiology.

  11. Arrhythmia - Multiple Languages

    Science.gov (United States)

    ... Supplements Videos & Tools You Are Here: Home → Multiple Languages → All Health Topics → Arrhythmia URL of this page: https://medlineplus.gov/languages/arrhythmia.html Other topics A-Z Expand Section ...

  12. Arrhythmia as a cardiac manifestation in MELAS syndrome

    Directory of Open Access Journals (Sweden)

    Tamara Thomas

    2015-09-01

    Full Text Available A 44-year-old female with a diagnosis of mitochondrial myopathy, encephalopathy and stroke-like episodes (MELAS syndrome had progressive left ventricular hypertrophy (LVH on echocardiogram. A Holter monitor demonstrated episodes of non-sustained atrial tachycardia, a finding not been previously described in this population. This unique case of MELAS syndrome demonstrates the known associated cardiac manifestation of LVH and the new finding of atrial tachycardia which may represent the potential for subclinical arrhythmia in this population.

  13. Common Tests for Arrhythmia

    Science.gov (United States)

    ... State SELECT YOUR LANGUAGE Español (Spanish) 简体中文 (Traditional Chinese) 繁体中文 (Simplified Chinese) Tiếng Việt (Vietnamese) Healthy Living for Heart.org ... help your doctor diagnose an arrhythmia. View an animation of arrhythmia . Common Tests for Arrhythmia Holter monitor ( ...

  14. Arrhythmias in Children in Early Postoperative Period After Cardiac Surgery.

    Science.gov (United States)

    Sahu, Manoj Kumar; Das, Anupam; Siddharth, Bharat; Talwar, Sachin; Singh, Sarvesh Pal; Abraham, Atul; Choudhury, Arin

    2018-01-01

    Postoperative arrhythmias are a known complication after cardiac surgical repairs for congenital heart disease. Data were reviewed pertaining to incidence, diagnosis, potential risk factors, and management of postoperative arrhythmias in 369 consecutive patients under 18 years of age, undergoing elective open heart surgery. All children were admitted to the intensive care unit and continuous electrocardiographic monitoring was performed. Patient factors such as Aristotle Basic Complexity Score, total surgical duration, hypotension, tachycardia, serum lactate level, and inotropic score were analyzed. Univariate analysis was done to assess associations between these factors and the occurrence of postoperative arrhythmias. Twenty-five (6.7%) patients developed arrhythmias. Junctional ectopic tachycardia (JET) was the most common arrhythmia occurring in 15 (60%) patients, followed by supraventricular tachycardia in 3 (12%), ventricular premature contractions in 3 (12%), hemodynamically unstable ventricular tachycardia and fibrillation in 3 (12%), and atrial fibrillation in 1 (4%) patient. Different grades of heart block were noted in 13 patients. Aristotle score (P = .014), total surgical duration (P postoperative period were associated with arrhythmia occurrence. Surgeries for ventricular septal defect alone or in association with other diseases including tetralogy of Fallot (TOF) and transposition of the great arteries (TGA) were found to be associated with higher risk of arrhythmias. This study showed a low incidence of arrhythmias, JET being the commonest, seen more in TOF repair and these could be treated efficiently. Higher Aristotle score, longer surgical time, hypotension, tachycardia, high inotropic score, and high serum lactate levels were associated with the occurrence of arrhythmias postoperatively.

  15. Recommendations for participation in leisure-time physical activity and competitive sports in patients with arrhythmias and potentially arrhythmogenic conditions Part I: Supraventricular arrhythmias and pacemakers.

    Science.gov (United States)

    Heidbüchel, Hein; Panhuyzen-Goedkoop, Nicole; Corrado, Domenico; Hoffmann, Ellen; Biffi, Allessandro; Delise, Pietro; Blomstrom-Lundqvist, Carina; Vanhees, Luc; Ivarhoff, Per; Dorwarth, Uwe; Pelliccia, Antonio

    2006-08-01

    This document by the Study Group on Sports Cardiology of the European Society of Cardiology extends on previous recommendations for sports participation for competitive athletes by also incorporating guidelines for those who want to perform recreational physical activity. For different supraventricular arrhythmias and arrhythmogenic conditions, a description of the relationship between the condition and physical activity is given, stressing how arrhythmias can be influenced by exertion or can be a reflection of the (patho)physiological cardiac adaptation to sports participation itself. The following topics are covered in this text: sinus bradycardia; atrioventricular nodal conduction disturbances; pacemakers; atrial premature beats; paroxysmal supraventricular tachycardia without pre-excitation; pre-excitation, asymptomatic or with associated arrhythmias (i.e. Wolff-Parkinson-White syndrome); atrial fibrillation; and atrial flutter. A related document discusses ventricular arrhythmias, channelopathies and implantable cardioverter defibrillators.

  16. Treatment of atrial fibrillation with radiofrequency ablation and simultaneous multipolar mapping of the pulmonary veins.

    Science.gov (United States)

    Rocha Neto, A C; Farias, R L; de Paola, A A

    2001-11-01

    To demonstrate the feasibility and safety of simultaneous catheterization and mapping of the 4 pulmonary veins for ablation of atrial fibrillation. Ten patients, 8 with paroxysmal atrial fibrillation and 2 with persistent atrial fibrillation, refractory to at least 2 antiarrhythmic drugs and without structural cardiopathy, were consecutively studied. Through the transseptal insertion of 2 long sheaths, 4 pulmonary veins were simultaneously catheterized with octapolar microcatheters. After identification of arrhythmogenic foci radiofrequency was applied under angiographic or ultrasonographic control. During 17 procedures, 40 pulmonary veins were mapped, 16 of which had local ectopic activity, related or not with the triggering of atrial fibrillation paroxysms. At the end of each procedure, suppression of arrhythmias was obtained in 8 patients, and elimination of pulmonary vein potentials was accomplished in 4. During the clinical follow-up of 9.6+/-3 months, 7 patients remained in sinus rhythm, 5 of whom were using antiarrhythmic drugs that had previously been ineffective. None of the patients had pulmonary hypertension or evidence of stenosis in the pulmonary veins. Selective and simultaneous catheterization of the 4 pulmonary veins with microcatheters for simultaneous recording of their electrical activity is a feasible and safe procedure that may help ablation of atrial fibrillation.

  17. Treatment of atrial fibrillation with radiofrequency ablation and simultaneous multipolar mapping of the pulmonary veins

    Directory of Open Access Journals (Sweden)

    Rocha Neto Almino C.

    2001-01-01

    Full Text Available OBJECTIVE: To demonstrate the feasibility and safety of simultaneous catheterization and mapping of the 4 pulmonary veins for ablation of atrial fibrillation. METHODS: Ten patients, 8 with paroxysmal atrial fibrillation and 2 with persistent atrial fibrillation, refractory to at least 2 antiarrhythmic drugs and without structural cardiopathy, were consecutively studied. Through the transseptal insertion of 2 long sheaths, 4 pulmonary veins were simultaneously catheterized with octapolar microcatheters. After identification of arrhythmogenic foci radiofrequency was applied under angiographic or ultrasonographic control. RESULTS: During 17 procedures, 40 pulmonary veins were mapped, 16 of which had local ectopic activity, related or not with the triggering of atrial fibrillation paroxysms. At the end of each procedure, suppression of arrhythmias was obtained in 8 patients, and elimination of pulmonary vein potentials was accomplished in 4. During the clinical follow-up of 9.6±3 months, 7 patients remained in sinus rhythm, 5 of whom were using antiarrhythmic drugs that had previously been ineffective. None of the patients had pulmonary hypertension or evidence of stenosis in the pulmonary veins. CONCLUSION: Selective and simultaneous catheterization of the 4 pulmonary veins with microcatheters for simultaneous recording of their electrical activity is a feasible and safe procedure that may help ablation of atrial fibrillation.

  18. Ischaemic stroke in hyperthyroidism without cardiac arrhythmia - A ...

    African Journals Online (AJOL)

    BACKGROUND: The relationship between hyperthyroidism and stroke is well established in the setting of atrial fibrillation. However there is limited literature for ischaemic stroke occurring in hyperthyroidism without cardiac arrhythmia. No such case had been described in South East Nigeria. METHOD: This report highlights ...

  19. Atrial fibrillation in elite athletes.

    Science.gov (United States)

    Furlanello, F; Bertoldi, A; Dallago, M; Galassi, A; Fernando, F; Biffi, A; Mazzone, P; Pappone, C; Chierchia, S

    1998-08-01

    Atrial fibrillation (AF) is a rare event in people younger than 25 years of age, but is probably more frequent in competitive athletes. We analyzed the presence of AF, paroxysmal or chronic, in a population of young elite athletes, including previous Olympic and World champions, who were studied for arrhythmias that endangered their athletic careers. From 1974 to June 1977, 1,772 athletes identified with arrhythmias (1,464 males and 308 females; mean age 21 years) underwent individualized work-ups. Among these, 146 (122 males and 24 females; mean age 24 years) were young elite athletes. They were studied from 1985 to 1997, with a mean follow-up of 62 months. Of the 146 young elite athletes, 13 (9%) had AF (paroxysmal in 11 and chronic in 2); all were male. The paroxysmal AF occurred during effort (n = 7), after effort (n = 1), or at rest (n = 3) and was reinduced by transesophageal pacing or endocavitary electrophysiologic testing under the same clinical circumstances. AF was the cause of symptoms in 13 (40%) of 22 young elite athletes with long-lasting palpitations. Five young elite athletes had a substrate for AF: Wolff-Parkinson-White syndrome (WPW) in 3, arrhythmogenic right ventricular dysplasia (ARVD) in 1, healed myocarditis in 1, and was considered idiopathic in 8. All elite athletes are alive with a mean follow-up of 62 months and 7 continue in their sports: 3 after radiofrequency catheter ablation (of WPW in 2 and AF with maze-type nonfluoroscopic approach in 1) and 4 after a period of de-training. AF, occurring in young elite athletes and affecting only males, is one of the most frequent causes of prolonged palpitations and is reproduced easily by transesophageal atrial pacing or electrophysiologic testing. AF may be a cause of disqualification from sports eligibility, but may disappear if the athletic activity is stopped for an adequate period of time, if trigger mechanisms are corrected (i.e., WPW), or if the substrate is modified.

  20. Comparative study of atrial fibrillation and AV conduction in mammals

    OpenAIRE

    Meijler, F L; van der Tweel, I

    1987-01-01

    Atrial fibrillation is one ofthe most common cardiac arrhythmias in humans. It a1so occurs quite frequent1y in dogs and horses. Comparative study of this arrhythmia may contribute to better understanding of the pathophysiologica1 mechanisms involved. In this study, we present a quantitative analysis of atrial fibrillation in humans, dogs, horses, and in a kangaroo, making use of histograms and serial autocorrelograms of the ventricular rhythm with and without digitalis medication. Increase in...

  1. Dofetilide in patients with congestive heart failure and left ventricular dysfunction: safety aspects and effect on atrial fibrillation. The Danish Investigators of Arrhythmia and Mortality on Dofetilide (DIAMOND) Study Group

    DEFF Research Database (Denmark)

    Møller, M; Torp-Pedersen, C T; Køber, L

    2002-01-01

    and reduced left ventricular systolic function were randomized to receive either placebo or a new class III antiarrhythmic drug, dofetilide. The dose of dofetilide was adjusted according to the presence of atrial fibrillation, the length of the QT interval, and renal function. Patients were continuously......INTRODUCTION. Atrial fibrillation is a frequent cause of worsening of symptoms in patients with congestive heart failure. The drugs currently available for maintenance of sinus rhythm all have major side effects. METHODS. In 34 Danish coronary care units, 1518 patients with congestive heart failure...

  2. Atrial fibrillation and female sex.

    Science.gov (United States)

    Anselmino, Matteo; Battaglia, Alberto; Gallo, Cristina; Gili, Sebastiano; Matta, Mario; Castagno, Davide; Ferraris, Federico; Giustetto, Carla; Gaita, Fiorenzo

    2015-12-01

    Atrial fibrillation is the most common supraventricular arrhythmia. Its prevalence increases with age and preferentially affects male patients. Over 75 years of age, however, female patients being more prevalent, the absolute number of patients affected is similar between sexes. Despite this, few data are available in the literature concerning sex-related differences in atrial fibrillation patients. The present systematic review therefore considers comorbidities, referring symptoms, quality of life, pharmacological approaches and trans-catheter ablation in female rather than in male atrial fibrillation patients in search of parameters that may have an impact on the treatment outcome. In brief, female atrial fibrillation patients more commonly present comorbidities, leading to a higher prevalence of persistent atrial fibrillation; moreover, they refer to hospital care later and with a longer disease history. Atrial fibrillation symptoms relate to low quality of life in female patients; in fact, atrial fibrillation paroxysm usually presents higher heart rate, leading to preferentially adopt a rate rather than a rhythm-control strategy. Female atrial fibrillation patients present an increased risk of stroke, worsened by the lower oral anticoagulant prescription rate related to the concomitant higher haemorrhagic risk profile. Trans-catheter ablation is under-used in female patients and, on the contrary, they are more commonly affected by anti-arrhythmic drug side effects.

  3. Drug-induced fatal arrhythmias: Acquired long QT and Brugada syndromes.

    Science.gov (United States)

    Turker, Isik; Ai, Tomohiko; Itoh, Hideki; Horie, Minoru

    2017-08-01

    Since the early 1990s, the concept of primary "inherited" arrhythmia syndromes or ion channelopathies has evolved rapidly as a result of revolutionary progresses made in molecular genetics. Alterations in genes coding for membrane proteins such as ion channels or their associated proteins responsible for the generation of cardiac action potentials (AP) have been shown to cause specific malfunctions which eventually lead to cardiac arrhythmias. These arrhythmic disorders include congenital long QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, short QT syndrome, progressive cardiac conduction disease, etc. Among these, long QT and Brugada syndromes are the most extensively studied, and drugs cause a phenocopy of these two diseases. To date, more than 10 different genes have been reported to be responsible for each syndrome. More recently, it was recognized that long QT syndrome can be latent, even in the presence of an unequivocally pathogenic mutation (silent mutation carrier). Co-existence of other pathological conditions in these silent mutation carriers may trigger a malignant form of ventricular arrhythmia, the so called torsade de pointes (TdP) that is most commonly brought about by drugs. In analogy to the drug-induced long QT syndrome, Brugada type 1 ECG can also be induced or unmasked by a wide variety of drugs and pathological conditions; so physicians may encounter patients with a latent form of Brugada syndrome. Of particular note, Brugada syndrome is frequently associated with atrial fibrillation whose therapeutic agents such as Vaughan Williams class IC drugs can unmask the dormant and asymptomatic Brugada syndrome. This review describes two types of drug-induced arrhythmias: the long QT and Brugada syndromes. Copyright © 2017. Published by Elsevier Inc.

  4. Transient T wave Changes Concerning Arrhythmia

    Directory of Open Access Journals (Sweden)

    Hirofumi Tasaki, MD PhD

    2007-01-01

    Full Text Available T-wave changes are thought to be associated with the repolarization phase of myocardial action potential. Although it has been known that persistent T-wave change is associated with the heart disease or the prognosis, the sensitivity and the specificity are not necessarily satisfactory for clinical therapeutic strategy. Recent basic studies have shown that, in some kinds of pathological states, transient repolarization changes of myocardial action potential were associated with life-threatening arrhythmia. Also clinical studies are being conducted to elucidate the clinical implication of transient T-wave changes on electrocardiography (ECG in such an arrhythmia. Transient repolarization or T-wave change is thought to occur because of environmental or neurohumoral factors, circadian variation, stretching of myocardium or other triggers in daily life, resulting in fatal arrhythmia. Such fatal arrhythmias are thought to occur under restricted conditions even in the patients with serious heart disease. It is important to clarify and utilize the transient T-wave change directly associated with the fatal arrhythmia on a clinical basis. In this article, we first assess the mechanisms of transient repolarization or T-wave changes on ECG concerning fatal arrhythmia, and afterwards refer to possible attempts at clinical evaluation and application.

  5. Comparative study of atrial fibrillation and AV conduction in mammals

    NARCIS (Netherlands)

    Meijler, F.L.; Tweel, I. van der

    1987-01-01

    Atrial fibrillation is one ofthe most common cardiac arrhythmias in humans. It a1so occurs quite frequent1y in dogs and horses. Comparative study of this arrhythmia may contribute to better understanding of the pathophysiologica1 mechanisms involved. In this study, we present a quantitative

  6. Why Arrhythmia Matters

    Science.gov (United States)

    ... State SELECT YOUR LANGUAGE Español (Spanish) 简体中文 (Traditional Chinese) 繁体中文 (Simplified Chinese) Tiếng Việt (Vietnamese) Healthy Living for Heart.org ... cardiac arrest Arrhythmias can cause stroke ( View an animation of arrhythmia ) Stroke is a cerebrovascular disease that ...

  7. Cardiac arrhythmias in pregnancy.

    Science.gov (United States)

    Knotts, Robert J; Garan, Hasan

    2014-08-01

    As more women with repaired congenital heart disease survive to their reproductive years and many other women are delaying pregnancy until later in life, a rising concern is the risk of cardiac arrhythmias during pregnancy. Naturally occurring cardiovascular changes during pregnancy increase the likelihood that a recurrence of a previously experienced cardiac arrhythmia or a de novo arrhythmia will occur. Arrhythmias should be thoroughly investigated to determine if there is a reversible etiology, and risks/benefits of treatment options should be fully explored. We discuss the approach to working up and treating various arrhythmias during pregnancy with attention to fetal and maternal risks as well as treatment of fetal arrhythmias. Acute management in stable patients includes close monitoring and intravenous pharmacologic therapy, while DC cardioversion should be used to terminate arrhythmias in hemodynamically unstable patients. Long-term management may require continued oral antiarrhythmic therapy, with particular attention to fetal safety, to prevent complications associated with arrhythmias. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Pharmacologic management of arrhythmias

    NARCIS (Netherlands)

    Bink-Boelkens, MTE

    2000-01-01

    The role of antiarrhythmic drugs in the management of children with arrhythmias has changed due to the rapid development of radiofrequency ablation. Moreover, the release of new drugs and a better insight into the electrophysiologic mechanisms of arrhythmias have changed former patterns of drug

  9. Cardiac arrhythmias in adult patients with asthma

    DEFF Research Database (Denmark)

    Warnier, Miriam J; Rutten, Frans H; Kors, Jan A

    2012-01-01

    OBJECTIVE: The pathogenesis of cardiac arrhythmias in asthma patients has not been fully elucidated. Adverse drug effects, particularly those of β2-mimetics, may play a role. The aim of this study was to determine whether asthma is associated with the risk of cardiac arrhythmias and electrocardio......OBJECTIVE: The pathogenesis of cardiac arrhythmias in asthma patients has not been fully elucidated. Adverse drug effects, particularly those of β2-mimetics, may play a role. The aim of this study was to determine whether asthma is associated with the risk of cardiac arrhythmias...... and electrocardiographic characteristics of arrhythmogenicity (ECG) and to explore the role of β2-mimetics. METHODS: A cross-sectional study was conducted among 158 adult patients with a diagnosis of asthma and 6303 participants without asthma from the cohort of the Utrecht Health Project-an ongoing, longitudinal, primary...... or flutter). Secondary outcomes were tachycardia, bradycardia, PVC, atrial fibrillation or flutter, mean heart rate, mean corrected QT (QTc) interval length, and prolonged QTc interval. RESULTS: Tachycardia and PVCs were more prevalent in patients with asthma (3% and 4%, respectively) than those without...

  10. Cardiac ion channels and mechanisms for protection against atrial fibrillation

    DEFF Research Database (Denmark)

    Grunnet, Morten; Bentzen, Bo Hjorth; Sørensen, Ulrik S

    2011-01-01

    Atrial fibrillation (AF) is recognised as the most common sustained cardiac arrhythmia in clinical practice. Ongoing drug development is aiming at obtaining atrial specific effects in order to prevent pro-arrhythmic, devastating ventricular effects. In principle, this is possible due to a different...

  11. Cardiac arrhythmias associated with umbilical venous catheterisation in neonates

    Science.gov (United States)

    Verheij, Gerdina; Smits-Wintjens, Vivianne; Rozendaal, Lieke; Blom, Nico; Walther, Frans; Lopriore, Enrico

    2009-01-01

    Umbilical venous catheters (UVCs) are commonly used in the management of severely ill neonates. Several life-threatening complications have been described, including catheter-related infections, myocardial perforation, pericardial effusion and cardiac arrhythmias. This report describe two neonates with cardiac arrhythmias due to umbilical venous catheterisation. One neonate had a supraventricular tachycardia requiring treatment with intravenous adenosine administration. Another neonate had an atrial flutter and was managed successfully with synchronised cardioversion. The primary cause of cardiac arrhythmias after umbilical venous catheterisation is inappropriate position of the UVC within the heart and the first step to treat them should be to pull back or even remove the catheter. Cardiac arrhythmia is a rare but potentially severe complication of umbilical venous catheterisation in neonates. PMID:21691401

  12. Advances in Left Atrial Appendage Occlusion Strategies

    OpenAIRE

    Arash Aryana; Sheldon M. Singh; Shephal K. Doshi; Andr� d�Avila

    2013-01-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and associated with an elevated risk of thromboembolic stroke and systemic embolization. The evidence suggests that ~90% of thrombi in patients with non-valvular AF are localized to the left atrial appendage (LAA). Therefore, it seems reasonable to consider LAA exclusion in selected patients with AF for stroke prevention. LAA exclusion can be achieved through a variety of surgical and percutaneous techniques. Surgical me...

  13. Innovation focus: the patient with arrhythmia.

    Science.gov (United States)

    Asirvatham, Samuel J

    2008-12-01

    Great strides have been made over the last two decades in the management of patients with rhythm disorders. Despite this, however, the remaining critical problems of stroke related to atrial fibrillation or as a result of radiofrequency ablation require innovative solutions to fully realize the potential of these recent advances. Similarly, implanted cardiac devices have revolutionized the care of patients with bradyrhythmias and tachyarrhythmias. Dyssynchronus ventricular pacing associated with present devices; however, results in heart failure, tricuspid regurgitation, and inappropriate device therapy once again create a demand for creative solutions. While not technically an arrhythmia, epilepsy management today is riddled with many of the problems that plagued cardiac arrhythmia management previously, and thus an appreciation of the similarities in requirement for investigative solutions may yield groundbreaking solutions. In this paper, we describe some novel methods to reduce complications associated with rhythm disorders and their treatment and apply the lessons learned from cardiovascular arrhythmia management to the brain. These include: a method to reduce coagulum formation and thus subsequent thromboembolism with indwelling catheters specifically during radiofrequency ablation procedures; a technique to ligate the left atrial appendage through percutaneous subxiphoid pericardial access; development and testing of a novel intramyocardial pace-sense lead, particularly used in a unique anatomic location (the atrioventricular septum) to allow pacing the ventricles in a relatively synchronous manner without crossing the tricuspid valve or entering the coronary sinus; finally, novel modifications of the cardiovascular mapping and ablation techniques used for the management of the central nervous system disorders primarily via the venous drainage of the brain. Innovative and potential solutions to treat the patient with arrhythmia are presented.

  14. Effectiveness of amiodarone in resistant arrhythmias.

    Science.gov (United States)

    Hollman, A; Holt, P M

    1980-12-01

    Amiodarone is used in the treatment of previously drug-resistant supraventricular and ventricular arrhythmias. We report our experience with amiodarone in 8 patients. Five patients had paroxysmal atrial flutter, one had paroxysmal atrial fibrillation, one had supraventricular tachycardia, and one ventricular tachycardia. Considerable improvement, both objectively and subjectively, was observed in all patients. Side effects were as follows: all patients had corneal microdeposits, one developed left bundle branch block which resolved on stopping amiodarone, and one reported constipation and abdominal pains. Six patients have been treated for 10-28 months; 3 developed tolerance at 4-14 months after the introduction of amiodarone therapy, but symptoms improved with increased dosage. It is important to watch for the development of tolerance to this drug.

  15. Effectiveness of amiodarone in resistant arrhythmias1

    Science.gov (United States)

    Hollman, Arthur; Holt, Phyllis M

    1980-01-01

    Amiodarone is used in the treatment of previously drug-resistant supraventricular and ventricular arrhythmias. We report our experience with amiodarone in 8 patients. Five patients had paroxysmal atrial flutter, one had paroxysmal atrial fibrillation, one had supraventricular tachycardia, and one ventricular tachycardia. Considerable improvement, both objectively and subjectively, was observed in all patients. Side effects were as follows: all patients had corneal microdeposits, one developed left bundle branch block which resolved on stopping amiodarone, and one reported constipation and abdominal pains. Six patients have been treated for 10–28 months; 3 developed tolerance at 4–14 months after the introduction of amiodarone therapy, but symptoms improved with increased dosage. It is important to watch for the development of tolerance to this drug. PMID:7452643

  16. Percutaneous transhepatic access for catheter ablation of cardiac arrhythmias.

    Science.gov (United States)

    Nguyen, Duy Thai; Gupta, Rajan; Kay, Joseph; Fagan, Thomas; Lowery, Christopher; Collins, Kathryn K; Sauer, William H

    2013-04-01

    Femoral venous access may be limited in certain patients undergoing electrophysiology (EP) study and ablation. The purpose of this study is to review a series of patients undergoing percutaneous transhepatic access to allow for ablation of cardiac arrhythmias. Six patients with a variety of cardiac arrhythmias and venous abnormalities underwent percutaneous transhepatic access. Under fluoroscopic and ultrasound guidance, a percutaneous needle was advanced into a hepatic vein and exchanged for a vascular sheath over a wire. Electrophysiology study and radiofrequency ablation was then performed. All tachycardias, including atrial tachycardia, atrial flutter, atrioventricular nodal tachycardia, and atrial fibrillation, were ablated. Procedural times ranged from 227 to 418 min. Fluoroscopy times ranged from 32 to 95 min. There were no complications. All six patients have been arrhythmia-free in follow-up (5-49 months, mean 23.1 months). Percutaneous transhepatic access is safe and feasible in patients with limited venous access who are undergoing EP study and ablation for a range of cardiac arrhythmias.

  17. Non-invasive localization of atrial ectopic beats by using simulated body surface P-wave integral maps.

    Science.gov (United States)

    Ferrer-Albero, Ana; Godoy, Eduardo J; Lozano, Miguel; Martínez-Mateu, Laura; Atienza, Felipe; Saiz, Javier; Sebastian, Rafael

    2017-01-01

    Non-invasive localization of continuous atrial ectopic beats remains a cornerstone for the treatment of atrial arrhythmias. The lack of accurate tools to guide electrophysiologists leads to an increase in the recurrence rate of ablation procedures. Existing approaches are based on the analysis of the P-waves main characteristics and the forward body surface potential maps (BSPMs) or on the inverse estimation of the electric activity of the heart from those BSPMs. These methods have not provided an efficient and systematic tool to localize ectopic triggers. In this work, we propose the use of machine learning techniques to spatially cluster and classify ectopic atrial foci into clearly differentiated atrial regions by using the body surface P-wave integral map (BSPiM) as a biomarker. Our simulated results show that ectopic foci with similar BSPiM naturally cluster into differentiated non-intersected atrial regions and that new patterns could be correctly classified with an accuracy of 97% when considering 2 clusters and 96% for 4 clusters. Our results also suggest that an increase in the number of clusters is feasible at the cost of decreasing accuracy.

  18. Electrophysiological Mechanisms of Atrial Flutter

    Directory of Open Access Journals (Sweden)

    Ching-Tai Tai

    2009-02-01

    Full Text Available Atrial flutter (AFL is a common arrhythmia in clinical practice. Several experimental models, such as tricuspid regurgitation model, tricuspid ring model, sterile pericarditis model and atrial crush injury model, have provided important information about reentrant circuit and can test the effects of antiarrhythmic drugs. Human AFL has typical and atypical forms. Typical AFL rotates around the tricuspid annulus and uses the crista terminalis and sometimes sinus venosa as the boundary. The tricuspid isthmus is a slow conduction zone and the target of radiofrequency ablation. Atypical AFL may arise from the right or left atrium. Right AFL includes upper loop reentry, free wall reentry and figure-of-8 reentry. Left AFL includes mitral annular AFL, pulmonary vein-related AFL and left septal AFL. Radiofrequency ablation of the isthmus between the boundaries can eliminate these arrhythmias.

  19. Incidence of ventricular arrhythmias, brady-arrhythmias and sudden ...

    African Journals Online (AJOL)

    Ventricular arrhythmias (VAS), Including ventricular tachycardia (VT), ventricular fibrillation (VF) and Brady-arrhythmias, are life-threatening complications of acute myocardial infarction (MI). Objective: To study the incidence of ventricular arrhythmias, brady-arrhythmias and Sudden Cardiac Death (SCD) in Sudanese ...

  20. Dofetilide: a new drug to control cardiac arrhythmia

    DEFF Research Database (Denmark)

    Elming, Hanne; Brendorp, Bente; Pedersen, Ole Dyg

    2003-01-01

    disease, and with prevalence increasing with age. A variety of drugs have been used to terminate or prevent AF but, as many antiarrhythmic agents have the potential life-threatening pro-arrhythmia, safety problems remain. Dofetilide (Tikosyn, Pfizer), a new Vaughan Williams class III antiarrhythmic agent......Atrial fibrillation (AF) is the most common cardiac arrhythmia. Mortality, and especially morbidity caused by AF, are major and growing health problems in the western world. AF is strongly associated with arterial hypertension, congestive heart failure, valvular heart disease, ischaemic heart...... and betablockers, dofetilide is the only antiarrhythmic drug, which is recommended by guidelines for the treatment of AF in a wide range of patients....

  1. Sports and arrhythmias.

    Science.gov (United States)

    Giada, F; Conte, R; Pescatore, V; Brugin, E

    2011-06-01

    Rhythm disorders represent the main challenge for the sport physician and cardiologist to grant the certificate of sports eligibility to the athletes. Arrhythmias that occur in athletes can be divided into two types. The most common are generally an expression of morphofunctional changes in the athlete's heart and are represented by certain forms of non-complex tachyarrhythmias and bradyarrhythmias. On the other hand you may encounter less frequently more complex arrhythmias that may be an epiphenomenon of cardiomyopathy can cause sudden death during sports activities. By collection of detailed medical history, careful examination, and in particular by the 12-lead electrocardiogram is already possible to understand the arrhythmic risk sporting population. After an analysis of main types of arrhythmias encountered in the athlete and the main diagnostic methods, this study focuses on the interplay between forms of arrhythmias, arrhythmogenic heart diseases and activity sports. Surely the increased adrenergic tone and anatomical and functional alterations sports-related favor the development of arrhythmia and sudden death risk in structural cardiomyopathies. But this is not yet resolved the question of whether sport is able to increase the incidence of ventricular arrhythmias in a normal heart. Dangerousness of the arrhythmia is variable depending on the sport is practiced with high intensity or not. Even if it is important considering the possibility of syncope in hazardous environments. Arrhythmias at risk impose the exclusion of the athlete from the practice of sport. In some cases it may be considered a drug treatment, ablation, and in rare and selected cases, the implantation of a pacemaker or an implantable defibrillator.

  2. Atrial Na,K-ATPase increase and potassium dysregulation accentuate the risk of postoperative atrial fibrillation

    DEFF Research Database (Denmark)

    Tran, Cao Thach; Schmidt, Thomas Andersen; Christensen, John Brochorst

    2009-01-01

    BACKGROUND: Postoperative atrial fibrillation is a common complication to cardiac surgery. Na,K-ATPase is of major importance for the resting membrane potential and action potential. The purpose of the present study was to evaluate the importance of Na,K-ATPase concentrations in human atrial...... biopsies and plasma potassium concentrations for the development of atrial fibrillation. METHODS: Atrial myocardial biopsies were obtained from 67 patients undergoing open chest cardiac surgery. Na,K-ATPase was quantified using vanadate-facilitated 3H-ouabain binding. Plasma potassium concentration...... with postoperative atrial fibrillation. CONCLUSIONS: The present study supports the increasing evidence of dysregulation of the potassium homeostasis as an important factor in the development of cardiac arrhythmias. High atrial Na,K-ATPase and sudden plasma potassium concentration increase may contribute...

  3. Catheter Ablation of Arrhythmias Exclusively Using Electroanatomic Mapping: A Series of Cases

    Science.gov (United States)

    Pires, Leonardo Martins; Leiria, Tiago Luiz Luz; Kruse, Marcelo Lapa; Ronsoni, Rafael; Gensas, Caroline Saltz; de Lima, Gustavo Glotz

    2013-01-01

    Background Catheter ablation is a treatment that can cure various cardiac arrhythmias. Fluoroscopy is used to locate and direct catheters to areas that cause arrhythmias. However, fluoroscopy has several risks. Electroanatomic mapping (EAM) facilitates three-dimensional imaging without X-rays, which reduces risks associated with fluoroscopy. Objective We describe a series of patient cases wherein cardiac arrhythmia ablation was exclusively performed using EAM. Methods Patients who presented with cardiac arrhythmias that were unresponsive to pharmacological therapy were prospectively selected between March 2011 and March 2012 for arrhythmia ablation exclusively through EAM. Patients with indications for a diagnostic electrophysiology study and ablation of atrial fibrillation, left atrial tachyarrhythmias as well as hemodynamically unstable ventricular arrhythmia were excluded. We documented the procedure time, success rate and complications as well as whether fluoroscopy was necessary during the procedure. Results In total, 11 patients were enrolled in the study, including seven female patients (63%). The mean age of the patients was 50 years (SD ±16.5). Indications for the investigated procedures included four cases (35%) of atrial flutter, three cases (27%) of pre-excitation syndrome, two cases (19%) of paroxysmal supraventricular tachycardia and two cases (19%) of ventricular extrasystoles. The mean procedure duration was 86.6 min (SD ± 26 min). Immediate success (at discharge) of the procedure was evident for nine patients (81%). There were no complications during the procedures. Conclusion This study demonstrates the feasibility of performing an arrhythmia ablation exclusively using EAM with satisfactory results. PMID:23877742

  4. Genetic aspects of lone atrial fibrillation

    DEFF Research Database (Denmark)

    Andreasen, Laura; Nielsen, Jonas B; Olesen, Morten S

    2015-01-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia. A subgroup of patients presents with AF without traditional risk factors and is diagnosed before the age of 60 years. Such patients are commonly referred as having "lone AF" and comprise 10-20% of all cases. A number of studies have ...

  5. Reduced incidence of cardiac arrhythmias in walkers and runners.

    Science.gov (United States)

    Williams, Paul T; Franklin, Barry A

    2013-01-01

    Walking is purported to reduce the risk of atrial fibrillation by 48%, whereas jogging is purported to increase its risk by 53%, suggesting a strong anti-arrhythmic benefit of walking over running. The purpose of these analyses is to compare incident self-reported physician-diagnosed cardiac arrhythmia to baseline energy expenditure (metabolic equivalent hours per day, METhr/d) from walking, running and other exercise. Proportional hazards analysis of 14,734 walkers and 32,073 runners. There were 1,060 incident cardiac arrhythmias (412 walkers, 648 runners) during 6.2 years of follow-up. The risk for incident cardiac arrhythmias declined 4.4% per baseline METhr/d walked by the walkers, or running in the runners (P = 0.0001). Specifically, the risk declined 14.2% (hazard ratio: 0.858) for 1.8 to 3.6 METhr/d, 26.5% for 3.6 to 5.4 METhr/d, and 31.7% for ≥5.4 METhr/d, relative to cardiac arrhythmias. Cardiac arrhythmias were unrelated to walking and running intensity, and unrelated to marathon participation and performance. The risk for cardiac arrhythmias was similar in walkers and runners who expended comparable METhr/d during structured exercise. We found no significant risk increase for self-reported cardiac arrhythmias associated with running distance, exercise intensity, or marathon participation. Rhythm abnormalities were based on self-report, precluding definitive categorization of the nature of the rhythm disturbance. However, even if the runners' arrhythmias include sinus bradycardia due to running itself, there was no increase in arrhythmias with greater running distance.

  6. Treating critical supraventricular and ventricular arrhythmias

    Directory of Open Access Journals (Sweden)

    Trappe Hans-Joachim

    2010-01-01

    Full Text Available Atrial fibrillation (AF, atrial flutter, AV-nodal reentry tachycardia with rapid ventricular response, atrial ectopic tachycardia and preexcitation syndromes combined with AF or ventricular tachyarrhythmias (VTA are typical arrhythmias in intensive care patients (pts. Most frequently, the diagnosis of the underlying arrhythmia is possible from the physical examination (PE, the response to maneuvers or drugs and the 12-lead surface electrocardiogram. In unstable hemodynamics, immediate DC-cardioversion is indicated. Conversion of AF to sinus rhythm (SR is possible using antiarrhythmic drugs. Amiodarone has a conversion rate in AF of up to 80%. Ibutilide represents a class III antiarrhythmic agent that has been reported to have conversion rates of 50-70%. Acute therapy of atrial flutter (Aflut in intensive care pts depends on the clinical presentation. Atrial flutter can most often be successfully cardioverted to SR with DC-energies < 50 joules. Ibutilide trials showed efficacy rates of 38-76% for conversion of Aflut to SR compared to conversion rates of 5-13% when intravenous flecainide, propafenone or verapamil was administered. In addition, high dose (2 mg of ibutilide was more effective than sotalol (1.5 mg/kg in conversion of Aflut to SR (70 versus 19%. Drugs like procainamide, sotalol, amiodarone or magnesium were recommended for treatment of VTA in intensive care pts. However, only amiodarone is today the drug of choice in VTA pts and also highly effective even in pts with defibrillation-resistant out-of-hospital cardiac arrest (CA. There is a general agreement that bystander first aid, defibrillation and advanced life support is essential for neurologic outcome in pts after cardiac arrest due to VTA. Public access defibrillation in the hands of trained laypersons seems to be an ideal approach in the treatment of ventricular fibrillation (VF. The use of automatic external defibrillators (AEDs by basic life support ambulance providers or

  7. Arrhythmias in the paediatric intensive care unit: a prospective study of the rates and predictors of arrhythmias in children without underlying cardiac disease.

    Science.gov (United States)

    Cassel-Choudhury, Gina N; Aydin, Scott I; Toedt-Pingel, Iris; Ushay, H Michael; Killinger, James S; Cohen, Hillel W; Ceresnak, Scott R

    2015-10-01

    Arrhythmias are common in patients admitted to the paediatric intensive care unit. We sought to identify the rates of occurrence and types of arrhythmias, and determine whether an arrhythmia was associated with illness severity and paediatric intensive care unit length of stay. This is a prospective, observational study of all patients admitted to the paediatric intensive care unit at the Children's Hospital at Montefiore from March to June 2012. Patients with cardiac disease or admitted for the treatment of primary arrhythmias were excluded. Clinical and laboratory data were collected and telemetry was reviewed daily. Tachyarrhythmias were identified as supraventricular tachycardia, ventricular tachycardia, and arrhythmias causing haemodynamic compromise or for which an intervention was performed. A total of 278 patients met the inclusion criteria and were analysed. There were 97 incidences of arrhythmia in 53 patients (19%) and six tachyarrhythmias (2%). The most common types of arrhythmias were junctional rhythm (38%), premature atrial contractions (24%), and premature ventricular contractions (22%). Tachyarrhythmias included three supraventricular tachycardia (50%) and three ventricular tachycardia (50%). Of the six tachyarrhythmias, four were related to placement or migration of central venous lines and two occurred during aminophylline infusion. Patients with an arrhythmia had longer duration of mechanical ventilation and paediatric intensive care unit stay (pintensive care unit patients (19%), although tachyarrhythmias occurred rarely (2%). Central venous lines and use of aminophylline were identified as two clinical factors that may be associated with development of an arrhythmia.

  8. Impact of left atrial size reduction on chronic atrial fibrillation in mitral valve surgery.

    Science.gov (United States)

    Scherer, Mirela; Dzemali, Omer; Aybek, Tayfun; Wimmer-Greinecker, Gerhard; Moritz, Anton

    2003-07-01

    Left atrial enlargement is a risk factor for the development of atrial fibrillation (AF). Large atrial size increases thromboembolic risk and reduces the success rate of cardioversion. The study aim was to evaluate if left atrial size reduction affects cardiac rhythm in patients with chronic AF undergoing mitral valve surgery. Twenty-seven patients were analyzed prospectively. The left atrial incision was extended to the left inferior pulmonary vein. Left atrial size reduction was achieved by closure of the left atrial appendage from inside with a double running suture. The same suture plicated the left lateral atrial wall to the roof of the left pulmonary vein inflow and the inferior atrial wall. The atrial septum was plicated by placing stitches of the closing suture line across the fossa ovalis. Rhythm, neurological complications, cardioversion, anticoagulation and anti-arrhythmic medication were evaluated at one year postoperatively and at recent follow up (mean 40 +/- 15 months). At discharge, five patients (19%) were in sinus rhythm (SR). At one year postoperatively, SR was restored in 17 patients (63%), but five (19%) reported episodes of arrhythmia and AF persisted in 10 (37%). At recent follow up, four patients had died and three were lost to follow up. Among 20 patients examined, 13 (65%) had SR but six reported episodes of arrhythmia and AF persisted in seven (35%). LA diameter was significantly reduced, from 60.2 +/- 9.8 mm preoperatively to 44.5 +/- 7.0 mm at one year after surgery. The addition of left atrial size reduction to mitral valve surgery is technically simple, and was effective in 63% of patients with chronic AF, restoring predominant SR. In order to influence pathogenetic factors other than size, additional ablative steps may further increase the SR conversion rate. Size reduction may also improve the outcome of other ablative approaches.

  9. The incidence and prognostic significance of cardiac arrhythmias and conduction abnormalities in patients with acute coronary syndromes and renal dysfunction.

    Science.gov (United States)

    Lisowska, Anna; Tycińska, Agnieszka; Knapp, Małgorzata; Lisowski, Piotr; Musiał, Włodzimierz J

    2011-01-01

    The incidence of cardiac arrhythmias, including atrial fibrillation (AF) in chronic kidney disease, is unknown, although AF is several times more common in patients with end-stage kidney disease than in the general population. To assess the incidence, types and management of cardiac arrhythmias and conduction abnormalities in patients with acute coronary syndromes (ACS) and renal dysfunction. We also evaluated the prognostic significance of arrhythmias in this patient group. We analysed 86 patients with renal dysfunction (GFR Cardiac arrhythmias were observed in 44 (51.1%) patients with AF being the most common (27 patients, 31.4%), predominantly in the paroxysmal form (21.4%). A total of 14 (16.3%) patients had cardiac arrhythmias requiring temporary or permanent pacing. Only 4 (4.6%) patients showed transient conduction abnormalities due to hyperkalaemia in the course of renal failure, while the remaining 10 (11.6%) patients demonstrated conduction abnormalities due to ACS. A total of 3 (3.5%) patients had other arrhythmias (atrial tachycardia, ventricular arrhythmias). During the follow-up period (mean duration: 14.3 months) 7 out of 44 patients (15.9%) with renal dysfunction and arrhythmia and 2 out of 42 patients (4.7%) without arrhythmia died (p Cardiac arrhythmias occur more often in patients with ACS if renal dysfunction is also present and are associated with poor prognosis.

  10. The Association between Nocturnal Cardiac Arrhythmias and Sleep-Disordered Breathing: The DREAM Study.

    Science.gov (United States)

    Selim, Bernardo J; Koo, Brian B; Qin, Li; Jeon, Sangchoon; Won, Christine; Redeker, Nancy S; Lampert, Rachel J; Concato, John P; Bravata, Dawn M; Ferguson, Jared; Strohl, Kingman; Bennett, Adam; Zinchuk, Andrey; Yaggi, Henry K

    2016-06-15

    To determine whether sleep-disordered breathing (SDB) is associated with cardiac arrhythmia in a clinic-based population with multiple cardiovascular comorbidities and severe SDB. This was a cross-sectional analysis of 697 veterans who underwent polysomnography for suspected SDB. SDB was categorized according to the apnea-hypopnea index (AHI): none (AHI cardiac arrhythmias consisted of: (1) complex ventricular ectopy, (CVE: non-sustained ventricular tachycardia, bigeminy, trigeminy, or quadrigeminy), (2) combined supraventricular tachycardia, (CST: atrial fibrillation or supraventricular tachycardia), (3) intraventricular conduction delay (ICD), (4) tachyarrhythmias (ventricular and supraventricular), and (5) any cardiac arrhythmia. Unadjusted, adjusted logistic regression, and Cochran-Armitage testing examined the association between SDB and cardiac arrhythmias. Linear regression models explored the association between hypoxia, arousals, and cardiac arrhythmias. Compared to those without SDB, patients with moderate-severe SDB had almost three-fold unadjusted odds of any cardiac arrhythmia (2.94; CI 95%, 2.01-4.30; p cardiac arrhythmias (2.24; 1.48-3.39; p = 0.004). Frequency of obstructive respiratory events and hypoxia were strong predictors of arrhythmia risk. SDB is independently associated with nocturnal cardiac arrhythmias. Increasing severity of SDB was associated with an increasing risk for any cardiac arrhythmia. © 2016 American Academy of Sleep Medicine.

  11. Role of adipose tissue in the pathogenesis of cardiac arrhythmias.

    Science.gov (United States)

    Samanta, Rahul; Pouliopoulos, Jim; Thiagalingam, Aravinda; Kovoor, Pramesh

    2016-01-01

    Epicardial adipose tissue is present in normal healthy individuals. It is a unique fat depot that, under physiologic conditions, plays a cardioprotective role. However, excess epicardial adipose tissue has been shown to be associated with prevalence and severity of atrial fibrillation. In arrhythmogenic right ventricular cardiomyopathy and myotonic dystrophy, fibrofatty infiltration of the myocardium is associated with ventricular arrhythmias. In the ovine model of ischemic cardiomyopathy, the presence of intramyocardial adipose or lipomatous metaplasia has been associated with increased propensity to ventricular tachycardia. These observations suggest a role of adipose tissue in the pathogenesis of cardiac arrhythmias. In this article, we review the role of cardiac adipose tissue in various cardiac arrhythmias and discuss the possible pathophysiologic mechanisms. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  12. Cardiac Arrhythmias in a Septic ICU Population: A Review

    Directory of Open Access Journals (Sweden)

    Schwartz Andrei

    2015-10-01

    Full Text Available Progressive cardiovascular deterioration plays a central role in the pathogenesis of multiple organ failure (MOF caused by sepsis. Evidence of various cardiac arrhythmias in septic patients has been reported in many published studies. In the critically ill septic patients, compared to non-septic patients, new onset atrial fibrillation episodes are associated with high mortality rates and poor outcomes, amongst others being new episodes of stroke, heart failure and long vasopressor usage. The potential mechanisms of the development of new cardiac arrhythmias in sepsis are complex and poorly understood. Cardiac arrhythmias in critically ill septic patients are most likely to be an indicator of the severity of pre-existing critical illness.

  13. Pharmacologic Therapy in the Elderly with Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Shih-Huang Lee

    2008-03-01

    Full Text Available Atrial fibrillation (AF is the most common sustained arrhythmia, and its prevalence significantly increases with age. Morphologic changes in the atrial myocardium associated with AF may result from underlying cardiovascular disease and/or physiologic aging processes. Congestive heart failure, tachycardia-induced cardiomyopathy and thromboembolic events resulting from AF are more common in elderly patients. It is important to assess any comorbidity and potential triggers of AF before considering pharmacologic therapy for AF. Proper rate control should include control in response to exercise, together with an avoidance of bradycardias and symptomatic pauses in patients with AF. Digoxin, β-blockers and calcium channel blockers can all be effective in controlling ventricular rate in elderly patients with AF. In the elderly, amiodarone is probably the safest drug for short-term administration to exert chemical cardioversion, facilitate electrical cardioversion, and prevent recurrence of AF. Warfarin has been shown to be highly effective in preventing stroke in the elderly with AF; however, many studies also have documented underuse of warfarin, may be because of the increased risk of warfarin-induced hemorrhage in such patients. These findings have raised concerns regarding quality of care, physician adherence to guidelines, and translation of clinical trial results into real-world practice in anticoagulation therapy in the elderly with AF. [International Journal of Gerontology 2008; 2(1: 1–6

  14. Mini-maze suffices as adjunct to mitral valve surgery in patients with preoperative atrial fibrillation

    NARCIS (Netherlands)

    Tuinenburg, AE; Van Gelder, IC; Tieleman, RG; Grandjean, JG; Huet, RCG; Van der Maaten, JMAA; Pieper, EG; De Kam, PJ; Ebels, MSCT; Crijns, HJGM

    Mini-Maze and Mitral Valve Surgery. Introduction: After mitral valve (MV) surgery, preoperative atrial fibrillation (AF) often recurs while cardioversion therapy generally fails. Additional Cox maze surgery improves postoperative arrhythmia outcome, but the extensive nature of such an approach

  15. Frequency of Cardiac Arrhythmias in Patients with Aluminum Phosphide Poisoning

    Directory of Open Access Journals (Sweden)

    Umair Aziz

    2015-12-01

    Full Text Available Background: Cardiac failure is the major lethal consequence of aluminum phosphide (AlP poisoning. This study was designed to determine the frequency of cardiac arrhythmias in patients with AlP poisoning. Methods: In this prospective cross-sectional study, patients with definitive history of AlP poisoning treated at emergency department of Allied Hospital Faisalabad, Faisalabad, Pakistan, from July 2013 to November 2014 were included. On admission, twelve-lead electrocardiogram (ECG was performed for all patients. During admission, all patients underwent continuous cardiac monitoring using a cardiac monitor. If an arrhythmia was suspected on the cardiac monitor, another ECG was obtained immediately.  Results: During the study period, 100 patients with AlP poisoning (63% men were treated at Allied Hospital Faisalabad. Mean age of the patients was 26.7 ± 7.9 years ranging from 16 to 54 years. Tachycardia was detected in 68 patients and bradycardia in 12 patients. Hypotension was observed in 75 patients. Eighty patients developed cardiac arrhythmia. The most frequent arrhythmia was atrial fibrillation (31% of patients followed by ventricular fibrillation (20%, ventricular tachycardia (17%, 3rd degree AV block (7% and 2nd degree AV block (5%. In total, 78 patients died, depicting a 78% mortality rate following wheat pill poisoning. Among those who died, seventy-one patients had cardiac arrhythmia. Comparison of death rate between patients with and without cardiac arrhythmia showed a significant difference (71/80 (88.8% vs. 7/20 (35%; P < 0.001.  Conclusion: Wheat pill poisoning causes a very high mortality, and circulatory collapse is the major cause of death among these patients. Most of the patients with AlP poisoning develop cardiac arrhythmias which are invariably life threatening. Early detection of cardiac disorders and proper management of arrhythmias may reduce mortalities.

  16. Effects of chronic atrial fibrillation on active and passive force generation in human atrial myofibrils.

    Science.gov (United States)

    Belus, Alexandra; Piroddi, Nicoletta; Ferrantini, Cecilia; Tesi, Chiara; Cazorla, Olivier; Toniolo, Luana; Drost, Maurice; Mearini, Giulia; Carrier, Lucie; Rossi, Alessandra; Mugelli, Alessandro; Cerbai, Elisabetta; van der Velden, Jolanda; Poggesi, Corrado

    2010-07-09

    Chronic atrial fibrillation (cAF) is associated with atrial contractile dysfunction. Sarcomere remodeling may contribute to this contractile disorder. Here, we use single atrial myofibrils and fast solution switching techniques to directly investigate the impact of cAF on myofilament mechanical function eliminating changes induced by the arrhythmia in atrial myocytes membranes and extracellular components. Remodeling of sarcomere proteins potentially related to the observed mechanical changes is also investigated. Myofibrils were isolated from atrial samples of 15 patients in sinus rhythm and 16 patients with cAF. Active tension changes following fast increase and decrease in [Ca(2+)] and the sarcomere length-passive tension relation were determined in the 2 groups of myofibrils. Compared to sinus rhythm myofibrils, cAF myofibrils showed (1) a reduction in maximum tension and in the rates of tension activation and relaxation; (2) an increase in myofilament Ca(2+) sensitivity; (3) a reduction in myofibril passive tension. The slow beta-myosin heavy chain isoform and the more compliant titin isoform N2BA were up regulated in cAF myofibrils. Phosphorylation of multiple myofilament proteins was increased in cAF as compared to sinus rhythm atrial myocardium. Alterations in active and passive tension generation at the sarcomere level, explained by translational and post-translational changes of multiple myofilament proteins, are part of the contractile dysfunction of human cAF and may contribute to the self-perpetuation of the arrhythmia and the development of atrial dilatation.

  17. Internal transvenous low energy cardioversion for the treatment of cardiac arrhythmias.

    OpenAIRE

    Nathan, A W; Bexton, R S; Spurrell, R A; Camm, A J

    1984-01-01

    Low energy endocardial cardioversion was attempted in 23 patients with 30 arrhythmias, of whom only four were receiving additional drug treatment. Four had atrial flutter, five atrial fibrillation, three intra-atrioventricular nodal tachycardia, two atrioventricular re-entrant tachycardia, 13 ventricular tachycardia, and three ventricular fibrillation. A pacing lead with special large surface area electrodes--the active electrode positioned either in the right atrium or in the right ventricul...

  18. Assessment of left atrial volume and function in patients with permanent atrial fibrillation

    DEFF Research Database (Denmark)

    Agner, Bue F Ross; Kühl, Jørgen Tobias; Linde, Jesper James

    2014-01-01

    Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with substantial morbidity and mortality. AF is associated with enlargement of the left atrium (LA), and the LA volume has important prognostic implications for the disease. The objective of the study was to determine how...

  19. Atrial tachyarrhythmia in adult congenital heart disease

    Science.gov (United States)

    Karbassi, Arsha; Nair, Krishnakumar; Harris, Louise; Wald, Rachel M; Roche, S Lucy

    2017-01-01

    The adult congenital heart disease (ACHD) population continues to grow and most cardiologists, emergency room physicians and family doctors will intermittently come into contact with these patients. Oftentimes this may be in the setting of a presentation with atrial tachyarrhythmia; one of the commonest late complications of ACHD and problem with potentially serious implications. Providing appropriate initial care and ongoing management of atrial tachyarrhythmia in ACHD patients requires a degree of specialist knowledge and an awareness of certain key issues. In ACHD, atrial tachyarrhythmia is usually related to the abnormal anatomy of the underlying heart defect and often occurs as a result of surgical scar or a consequence of residual hemodynamic or electrical disturbances. Arrhythmias significantly increase mortality and morbidity in ACHD and are the most frequent reason for ACHD hospitalization. Intra-atrial reentrant tachycardia and atrial fibrillation are the most prevalent type of arrhythmia in this patient group. In hemodynamically unstable patients, urgent cardioversion is required. Acute management of the stable patient includes anticoagulation, rate control, and electrical or pharmacological cardioversion. In ACHD, rhythm control is the preferred management strategy and can often be achieved. However, in the long-term, medication side-effects can prove problematic. Electrophysiology studies and catheter ablation are important treatments modalities and in certain cases, surgical or percutaneous treatment of the underlying cardiac defect has a role. ACHD patients, especially those with complex CHD, are at increased risk of thromboembolic events and anticoagulation is usually required. Female ACHD patients of child bearing age may wish to pursue pregnancies. The risk of atrial arrhythmias is increased during pregnancy and management of atrial tachyarrhythmia during pregnancy needs specific consideration. PMID:28706585

  20. Burden of Arrhythmias in Epilepsy Patients: A Nationwide Inpatient Analysis of 1.4 Million Hospitalizations in the United States.

    Science.gov (United States)

    Desai, Rupak; Rupareliya, Chintan; Patel, Upenkumar; Naqvi, Syeda; Patel, Smit; Lunagariya, Abhishek; Mahuwala, Zabeen

    2017-08-08

    Arrhythmias have been one of the common complications in epilepsy patients and have also been the reason for death. However, limited data exist about the burden and outcomes of arrhythmias by subtypes in epilepsy. Our study aims at evaluating the burden and differences in outcomes of various subtypes of arrhythmias in epilepsy patient population. The Nationwide Inpatient Sample (NIS) database from 2014 was examined for epilepsy and arrhythmias related discharges using appropriate International Classification of Disease, Ninth Revision Clinical Modification (ICD-9-CM) codes. The frequency of arrhythmias, gender differences in arrhythmia by subtypes, in-hospital outcomes and mortality predictors was analyzed. A total of 1,424,320 weighted epilepsy patients was determined and included in this study. Around 23.9% (n =277,230) patients had cardiac arrhythmias. The most frequent arrhythmias in the descending frequency were: atrial fibrillation (AFib) 9.7%, other unspecified causes 7.3%, sudden cardiac arrest (SCA) 1.4%, bundle branch block (BBB) 1.2%, ventricular tachycardia (VT) 1%. Males were more predisposed to cardiac arrhythmias compared to females (OR [odds ratio]: 1.1, p epilepsy. Life threatening arrhythmias were more common in male patients. The length of stay (LOS) and mortality were significantly higher in epilepsy patients with arrhythmia. It is imperative to develop early diagnosis and prompt therapeutic measures to reduce this burden and poor outcomes due to concomitant arrhythmias in epilepsy patients.

  1. Effects of novel oral anticoagulants on left atrial and left atrial appendage thrombi: an appraisal.

    Science.gov (United States)

    Marsico, Fabio; Cecere, Milena; Parente, Antonio; Paolillo, Stefania; de Martino, Fabiana; Dellegrottaglie, Santo; Trimarco, Bruno; Perrone Filardi, Pasquale

    2017-02-01

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and predisposes to an increased risk of thromboembolic events. Patients affected by AF exhibit an increased risk of stroke compared with those in sinus rhythm, with the most common location of thrombi in the left atrial appendage. Until 2009, warfarin and other vitamin K antagonists were the only class of oral anticoagulants available. More recently, dabigatran, rivaroxaban, apixaban, and edoxaban have been approved by regulatory authorities for prevention of stroke in patients with non-valvular AF. Few data are available about the efficacy of novel oral anticoagulants for the treatment of left atrial and left atrial appendage thrombosis. Aim of this review is to summarize available evidence regarding the effectiveness of novel oral anticoagulants on left atrial appendage thrombosis.

  2. The implications of obesity for cardiac arrhythmia mechanisms and management.

    Science.gov (United States)

    Pathak, Rajeev K; Mahajan, Rajiv; Lau, Dennis H; Sanders, Prashanthan

    2015-02-01

    The ever-increasing prevalence of obesity poses a significant burden on the health care system with escalating socioeconomic consequences. At the individual level, obesity is well recognized to increase morbidity and mortality. Not only is obesity an established cardiovascular risk factor, it also increases the risk of sudden cardiac death and atrial fibrillation. Studies have shown that increased adiposity itself and the accompanying metabolic consequences of weight gain contribute to an abnormal arrhythmogenic substrate. In this review, we focus on the diverse mechanisms underlying cardiac arrhythmias related to obesity. In particular, we highlight the pathogenic role of adipose depots leading to increased atrial fibrillation and the effect of weight reduction in decreasing atrial fibrillation burden in obese individuals. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  3. HYPERTHYROIDISM AND ATRIAL FIBRILLATION

    Directory of Open Access Journals (Sweden)

    I. M. Marusenko

    2017-01-01

    Full Text Available Review on a problem of the development of atrial fibrillation in patients with thyrotoxicosis is presented. Thyrotoxicosis is one of the most frequent endocrine diseases, conceding only to a diabetes mellitus. The most frequent reasons of hyperthyroidism are Graves’ disease and functional thyroid autonomy. The authors give an analysis of data on the cardiac effects of thyrotoxicosis, features of heart remodeling under the influence of thyroid hyperfunction, prevalence of atrial fibrillation in thyrotoxicosis, depending on age, as well as the possibility of restoring sinus rhythm in the combination of these diseases. Particular attention is paid to the effect on the heart of subclinical thyrotoxicosis, which is defined as a dysfunction of the thyroid gland, characterized by low serum concentration of thyrotropin, normal values of free thyroxine and free triiodothyronine. Subclinical hyperthyroidism is also capable of causing heart remodeling and diastolic dysfunction.Prevalence of thyrotoxicosis in elderly people is higher in areas of iodine deficiency; it is relevant for our country due to the large territory of iodine deficiency. In elderly patients, the cardiac effects of thyrotoxicosis prevail in the clinical picture, that makes it difficult to diagnose endocrine disorders, and correction of thyrotoxicosis is critically important for the successful control of the heart rhythm. The article also discusses the problem of thyrotoxic cardiomyopathy, caused by the toxic effect of excess thyroid hormones: features of this heart disorder, factors affecting its formation, clinical significance and contribution to the development of rhythm disturbances. The greatest significance is the development of atrial fibrillation as a result of thyrotox-icosis in older patients who already have various cardiovascular diseases.Atrial fibrillation is the most frequent heart rhythm disorder in thyrotoxicosis. The main cause of arrhythmia in hyperthyroidism is the

  4. Analysis of adults with congenital heart disease presenting to pediatric emergency departments with arrhythmias.

    Science.gov (United States)

    Mohan, Shaun; Moffett, Brady S; Lam, Wilson; de la Uz, Caridad; Miyake, Christina; Valdes, Santiago O; Kim, Jeffrey J

    2017-07-01

    As survivors of congenital heart disease (CHD) continue to age, healthcare utilization by this population has increased. It is unknown how often these patients utilize the emergency department (ED) at children's hospitals and how arrhythmias play a role in their utilization of care. Using a retrospective cohort design, the Pediatric Hospital Information System (PHIS) database was investigated and we studied adults (≥18 years) with CHD (ACHD) who presented to pediatric EDs from 2004 to 2014. Tertiary care pediatric hospitals. Of the 6310 encounters to pediatric EDs, 1594 (25%) were for arrhythmias. The median age was 21 years (IQR 19.1-25.1). The most common tachyarrhythmia diagnoses during the study period were atrial flutter (32%), atrial fibrillation (15%), and paroxysmal VT (10%). Bradyarrhythmias represented a minority of total arrhythmias. Presentation with arrhythmias was associated with an increased risk of admission, ICU care, and death (P pediatric EDs for this cohort has increased. Adults with higher CHD complexity are more likely to present with clinical arrhythmias but there is a growing number of ACHD patients with simple complexity presenting with arrhythmias in recent years. ACHD patients that present with arrhythmias are at increased risk of morbidity and mortality. © 2017 Wiley Periodicals, Inc.

  5. POSTOPERATIVE ATRIAL FIBRILLATION – AN UPDATE

    Directory of Open Access Journals (Sweden)

    Johnson Francis

    2015-12-01

    Full Text Available Atrial fibrillation is the most common perioperative cardiac arrhythmia. Sympathetic overactivity, inflammatory state and oxidative stress are important contributors to the genesis of postoperative atrial fibrillation. Advancing age and mitral valve disease along with left atrial size are important parameters in noted in multivariate prediction model. Genetic predisposition has also been noted. Preventive strategies tried include beta blockers, statins, posterior pericardiotomy, carperitide infusion and thoracic epidural analgesia. Treatment options include rate and rhythm control along with anticoagulation if it persists more than 48 hours with high CHADS2 score. Some of the therapeutic modalities which have been found to be NOT useful in preventing post operative atrial fibrillation are dexamethasone, magnesium infusion and concomitant pulmonary vein isolation.

  6. [Psychosomatic aspects of cardiac arrhythmias].

    Science.gov (United States)

    Siepmann, Martin; Kirch, Wilhelm

    2010-07-01

    Emotional stress facilitates the occurrence of cardiac arrhythmias including sudden cardiac death. The prevalence of anxiety and depression is increased in cardiac patients as compared to the normal population. The risk of cardiovascular mortality is enhanced in patients suffering from depression. Comorbid anxiety disorders worsen the course of cardiac arrhythmias. Disturbance of neurocardiac regulation with predominance of the sympathetic tone is hypothesized to be causative for this. The emotional reaction to cardiac arrhythmias is differing to a large extent between individuals. Emotional stress may result from coping with treatment of cardiac arrhythmias. Emotional stress and cardiac arrhythmias may influence each other in the sense of a vicious circle. Somatoform cardiac arrhythmias are predominantly of psychogenic origin. Instrumental measures and frequent contacts between physicians and patients may facilitate disease chronification. The present review is dealing with the multifaceted relationships between cardiac arrhythmias and emotional stress. The underlying mechanisms and corresponding treatment modalities are discussed.

  7. Atrial fibrillation after taser exposure in a previously healthy adolescent.

    Science.gov (United States)

    Multerer, Sara; Berkenbosch, John W; Das, Bibhuti; Johnsrude, Christopher

    2009-12-01

    We are reporting a previously healthy adolescent who developed atrial fibrillation after being tased. He has a structurally normal heart on echocardiogram, normal electrolyte level and thyroid function test results, and a urine toxicology screen positive for marijuana. The patient ultimately required external defibrillation to convert his cardiac rhythm to normal sinus rhythm and has had no recurrent arrhythmias since hospital discharge (approximately 1 year). This is the first reported case of atrial fibrillation developing after a Taser shot, occurring in an adolescent without other risk factors. This case illustrates the arrhythmogenic potential of a Taser in otherwise healthy young individuals, and further study of occurrence of Taser-induced arrhythmias is warranted.

  8. Positive pressure therapy in patients with cardiac arrhythmias and obstructive sleep apnea.

    Science.gov (United States)

    Dediu, Giorgiana Nicoleta; Dumitrache-Rujinski, Stefan; Lungu, Rizvan; Frunză, Sabina; Diaconu, Camelia; Bartoş, Daniela; Bogdan, Miron Alexandru

    2015-01-01

    Positive pressure therapy (CPAP) in patients with cardiac arrhythmias and obstructive sleep apnea (OSAS) may have favorable effects by correcting intermittent hypoxemia and sympathetic activation. To assess the effect of CPAP added to pharmacological treatment in the rate control and prevention of arrhythmias recurrence in patients with OSA. Prospective, interventional study study which included patients diagnosed with OSAS (cardiorespiratorypolygraphy, AHI>5/hour), and arrhythmias (ECG, Holter ECG), divided in two groups: group A (pharmacological therapy only) and group B (pharmacological therapy and CPAP). The patients were evaluated at enrollment (T0), at 3 and 6 months (T3 and T6) regarding the type, severity and recurrence of cardiac arrhythmias. 36 patients (31 men), mean age: 63.2 ± 12 years were enroled. In group A: 7 patients with ventricular extrasystoles, 8 with permanent atrial fibrillation, 1 patient with atrial flutter and 2 patients with paroxystic supraventricular tachycardia. In group B: 8 patients with ventricular extrasystoles, 5 with permanent atrial fibrillation, 2 patients with recurrent episodes of atrial fibrillation and 3 with paroxystic supraventricular tachycardia. A positive correlation (r: 0.74, p < 0.001) between Oxygen Desaturation Index and AHI was found. At T6, 12 patients from group B, and 18 from group A were evaluated. In group B, the mean heart rate in patients with atrial fibrillation was 69/min., lower than in group A (82/min.), no cases with recurrent atrial fibrillation were found, and more patients with class II Lown ventricular extrasystoles passed in class I Lown, compared to group A. In group B, heart rate statistically correlated with AHI (r: 0.53, p < 0.005). In patients with OSAS, adding CPAP to pharmacological therapy has favorable effects on preventing recurrences, heart rate control in patients with atrial fibrillation and in reducing frequency and/or severity of ventricular extrasystoles.

  9. Effect of ethanol at clinically relevant concentrations on atrial inward rectifier potassium current sensitive to acetylcholine

    Czech Academy of Sciences Publication Activity Database

    Bébarová, M.; Matejovič, P.; Pásek, Michal; Hořáková, Z.; Hošek, J.; Šimurdová, M.; Šimurda, J.

    2016-01-01

    Roč. 389, č. 10 (2016), s. 1049-1058 ISSN 0028-1298 Institutional support: RVO:61388998 Keywords : arrhythmias * atrial cardiomyocyte * inward rectifier potasssium current * ethanol * rat atrial cell model Subject RIV: BO - Biophysics Impact factor: 2.558, year: 2016

  10. The Role of Thyroid Hormones in the Development of Atrial Fibrillation in Thyroid Pathology

    Directory of Open Access Journals (Sweden)

    B.A. Rebrov

    2014-04-01

    Full Text Available The article describes the effects of thyroid hormones on the cardiovascular system, their role in the development of cardiac arrhythmias and, particularly, atrial fibrillation. The clinical manifestations and current guidelines for the treatment of thyroid diseases in combination with atrial fibrillation are provided.

  11. Right Atrial Appendage Aneurysm in a Newborn Diagnosed with Fetal Echocardiography

    Science.gov (United States)

    Yartaşı Tik, Elif; Öztarhan, Kazım; Dedeoğlu, Reyhan; Çetinkaya, Merih

    2016-01-01

    Right atrial appendage aneurysm is a very rare condition which can be asymptomatic or can cause arrhythmia or life-threatening thromboembolism. We report a case of newborn with right atrial appendage aneurysm who was diagnosed with fetal echocardiography. Anticoagulant therapy was applied to prevent thromboembolism and he is still going on follow-up without any complaint. PMID:27703828

  12. Almanac 2013: cardiac arrhythmias and pacing.

    Science.gov (United States)

    Liew, Reginald

    2013-10-01

    Important advances have been made in the past few years in the fields of clinical cardiac electrophysiology and pacing. Researchers and clinicians have a greater understanding of the pathophysiological mechanisms underlying atrial fibrillation (AF), which has transpired into improved methods of detection, risk stratification, and treatments. The introduction of novel oral anticoagulants has provided clinicians with alternative options in managing patients with AF at moderate to high thromboembolic risk and further data has been emerging on the use of catheter ablation for the treatment of symptomatic AF. Another area of intense research in the field of cardiac arrhythmias and pacing is in the use of cardiac resynchronisation therapy (CRT) for the treatment of patients with heart failure. Following the publication of major landmark randomised controlled trials reporting that CRT confers a survival advantage in patients with severe heart failure and improves symptoms, many subsequent studies have been performed to further refine the selection of patients for CRT and determine the clinical characteristics associated with a favourable response. The field of sudden cardiac death and implantable cardioverter defibrillators also continues to be actively researched, with important new epidemiological and clinical data emerging on improved methods for patient selection, risk stratification, and management. This review covers the major recent advances in these areas related to cardiac arrhythmias and pacing.

  13. THE USE OF OMEGA-3 FATTY ACIDS FOR THE TREATMENT OF PATIENTS WITH CARDIAC ARRHYTHMIAS

    Directory of Open Access Journals (Sweden)

    A. O. Malygin

    2013-01-01

    Full Text Available Antiarrhythmic effect of omega-3 polyunsaturated fatty acids (ω-3 PUFA, eicosapentaenoic and docosahexaenoic acids in patients with recurrent atrial fibrillation and ventricular arrhythmias had been proven. The positive effect of the ω-3 PUFA on the risk of sudden arrhythmic death and overall mortality in the patients after myocardial infarction and patients with chronic heart failure had been also proven.

  14. THE USE OF OMEGA-3 FATTY ACIDS FOR THE TREATMENT OF PATIENTS WITH CARDIAC ARRHYTHMIAS

    Directory of Open Access Journals (Sweden)

    A. O. Malygin

    2015-09-01

    Full Text Available Antiarrhythmic effect of omega-3 polyunsaturated fatty acids (ω-3 PUFA, eicosapentaenoic and docosahexaenoic acids in patients with recurrent atrial fibrillation and ventricular arrhythmias had been proven. The positive effect of the ω-3 PUFA on the risk of sudden arrhythmic death and overall mortality in the patients after myocardial infarction and patients with chronic heart failure had been also proven.

  15. Hybrid Therapy in the Management of Atrial Fibrillation

    OpenAIRE

    St?rek, Zden?k; Lehar, Franti?ek; Je?, Ji??; Wolf, Ji??; Nov?k, Miroslav

    2015-01-01

    Atrial fibrillation is the most common sustained arrhythmia. Because of the sub-optimal outcomes and associated risks of medical therapy as well as the recent advances in non-pharmacologic strategies, a multitude of combined (hybrid) algorithms have been introduced that improve efficacy of standalone therapies while maintaining a high safety profile. Antiarrhythmic administration enhances success rate of electrical cardioversion. Catheter ablation of antiarrhythmic drug-induced typical atrial...

  16. Cetirizine-Induced atrial fibrillation

    Directory of Open Access Journals (Sweden)

    Altuğ Osken

    2016-01-01

    Full Text Available Atrial fibrillation (AF is the most common observed arrhythmia in clinical practice. In the literature, AF events associated with drug induction are available. Cetirizine is a second-generation histamine antagonist used in the treatment of allergies, angioedema, and urticaria. We wish to present an atypical case who took cetirizine medication for relieving symptoms of upper tract respiratory system infection, experienced rapid ventricular response AF and treated successfully. To best of our knowledge, this is the first case of cetirizine-induced AF.

  17. Systems biology and cardiac arrhythmias.

    Science.gov (United States)

    Grace, Andrew A; Roden, Dan M

    2012-10-27

    During the past few years, the development of effective, empirical technologies for treatment of cardiac arrhythmias has exceeded the pace at which detailed knowledge of the underlying biology has accumulated. As a result, although some clinical arrhythmias can be cured with techniques such as catheter ablation, drug treatment and prediction of the risk of sudden death remain fairly primitive. The identification of key candidate genes for monogenic arrhythmia syndromes shows that to bring basic biology to the clinic is a powerful approach. Increasingly sophisticated experimental models and methods of measurement, including stem cell-based models of human cardiac arrhythmias, are being deployed to study how perturbations in several biologic pathways can result in an arrhythmia-prone heart. The biology of arrhythmia is largely quantifiable, which allows for systematic analysis that could transform treatment strategies that are often still empirical into management based on molecular evidence. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Cardiac Arrhythmias and Sleep-Disordered Breathing in Patients with Heart Failure

    Science.gov (United States)

    Grimm, Wolfram; Koehler, Ulrich

    2014-01-01

    The relationship between heart failure (HF), sleep-disordered breathing and cardiac arrhythmias is complex and poorly understood. Whereas the frequency of predominantly obstructive sleep apnea in HF patients is low and similar or moderately higher to that observed in the general population, central sleep apnea (CSA) has been observed in approximately 50% of HF patients, depending on the methods used to detect CSA and patient selection. Despite this high prevalence, it is still unclear whether CSA is merely a marker or an independent risk factor for an adverse prognosis in HF patients and whether CSA is associated with an increased risk for supraventricular as well as ventricular arrhythmias in HF patients. The current review focuses on the relationship between CSA and atrial fibrillation as the most common atrial arrhythmia in HF patients, and on the relationship between CSA and ventricular tachycardia and ventricular fibrillation as the most frequent cause of sudden cardiac death in HF patients. PMID:25325536

  19. The conundrum of ventricular arrhythmia and cardiomyopathy: which abnormality came first?

    Science.gov (United States)

    Bhushan, Mishi; Asirvatham, Samuel J

    2009-03-01

    Ventricular arrhythmia and cardiomyopathy often coexist. Many patients with abnormal ventricular function have either documented premature ventricular contractions (PVCs) or nonsustained ventricular tachycardia and have an increased risk of sudden death from ventricular fibrillation. Tachycardia is a treatable cause of cardiomyopathy. The culprit arrhythmia may be atrial tachycardia, atrial fibrillation, or another supraventricular arrhythmia. The syndrome of PVCs giving rise to ventricular dysfunction was recently described. Thus, a conundrum exists for clinicians in determining which abnormality (PVCs or cardiomyopathy) came first and gave rise to the other. Solving this dilemma is important because radiofrequency ablation for frequent PVCs can completely reverse the cardiomyopathy and normalize systolic ventricular function. In this article, we describe the present evidence for the syndrome of PVCs that can be ablated as a cause for cardiomyopathy. We include a case example and discussion to illustrate this concept and provide a stepwise approach to determining whether PVCs cause cardiomyopathy or vice versa.

  20. Pathogenic Mechanisms of Atrial Fibrillation in Obesity

    Directory of Open Access Journals (Sweden)

    O. M. Drapkina

    2016-01-01

    Full Text Available Atrial fibrillation (AF is one of the most common arrhythmias. It reduces quality of life and its duration due to thromboembolic complications. Obesity contributes to the structural and electrical remodeling of atrial myocardium. This leads to occurrence of ectopic foci in the mouths of the pulmonary veins and the disruption of normal electrical conduction in the atria. Systemic inflammation, myocardial fibrosis, cardiomyocyte overload by Na+ and Ca2+ ions, accumulation in the cells of unoxidized metabolic products, imbalance of the autonomic regulation are considered as the main mechanisms of arrhythmogenic substrate formation. Hypertension, insulin resistance, and obstructive sleep apnea, associated with obesity, increase the risk of development and progression of the arrhythmia. Study of pathogenetic mechanisms of AF in obesity is necessary to develop new strategies for its prevention and the creation of more effective methods of treatment of these patients.

  1. Antiarrhythmic therapeutic effect ofpolyunsaturated omega-3 fatty acids used in treatment ofventricular arrhythmia in 15-year-old female swimmer – case report

    Directory of Open Access Journals (Sweden)

    Zbigniew Krenc

    2015-03-01

    Full Text Available Premature ventricular contractions are common, both in the general population and among athletes. These arrhythmias are characterized by a heterogeneous aetiology and different clinical significance. They may develop not only as a sign of structural heart disease (e.g. myocarditis, cardiomyopathy, myocardial ischaemia, heart defects, genetically determined ion channel dysfunctions, but also as a result of electrolyte imbalances and adverse effects of pharmacotherapy. However, it is not possible to determine their causes in some of the patients. Premature ventricular contractions in patients with heart disease may be a trigger for life-threatening arrhythmias, especially during physical exercise. Antiarrhythmic agents having various mechanisms of  action, particularly β-adrenergic blocking agents and, in some cases, invasive procedures such as ablation of  an arrhythmogenic focus, are used for the treatment of ventricular arrhythmias. Some of the dietary supplements, polyunsaturated omega-3 fatty acids in particular, may also be effective. Epidemiological and experimental studies as well as randomized clinical trials indicate that n-3 polyunsaturated fatty acids show antiarrhythmic properties by direct effects on electrophysical processes in cardiomyocytes – both atrial and ventricular. Omega-3 polyunsaturated fatty acids were observed to have, among other things, the following effects: inhibiting some of the ionic currents (sodium, L-type calcium, potassium, increasing parasympathetic tone and decreasing the sensitivity of β-adrenergic receptors. This paper presents a case of idiopathic ventricular arrhythmia in a 15-year-old female swimmer successfully treated with n-3 polyunsaturated fatty acids.

  2. The risk of arrhythmias following coronary artery bypass surgery: do smokers have a paradox effect?

    LENUS (Irish Health Repository)

    Al-Sarraf, Nael

    2010-11-01

    Smoking is reported to increase the risk of arrhythmias. However, there are limited data on its effects on arrhythmias following coronary artery bypass graft (CABG). This is a retrospective review of a prospective database of all CABG patients over an eight-year period. Our cohort (n=2813) was subdivided into: current (n=1169), former (n=837), and non-smokers (n=807). Predictors of arrhythmias following CABG in relation to smoking status were analysed. Atrial arrhythmias occurred in 942 patients (33%). Ventricular arrhythmias occurred in 48 patients (2%) and high-grade atrioventricular block occurred in five patients (0.2%). Arrhythmias were lower in current smokers than former and non-smokers (29% vs. 40% vs. 39%, respectively P<0.001). Logistic regression analysis showed 30% arrhythmia risk reduction in smokers compared to non-smokers [odds ratio (OR) 0.7, 95% confidence intervals (CI) 0.5-0.8] and this effect persisted after accounting for potential confounders while former smokers had the same risk as non-smokers (OR 1.04, CI 0.9-1.3). There were no significant differences in mortality. Smokers are less prone to develop arrhythmias following CABG. This paradox effect is lost in former smokers. This effect is possibly due to a lower state of hyper adrenergic stimulation observed in smokers than non-smokers following the stress of surgery.

  3. Acute atrial fibrillation during dengue hemorrhagic fever

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    Veloso Henrique Horta

    2003-01-01

    Full Text Available Dengue fever is a viral infection transmitted by the mosquito, Aedes aegypti. Cardiac rhythm disorders, such as atrioventricular blocks and ventricular ectopic beats, appear during infection and are attributed to viral myocarditis. However, supraventricular arrhythmias have not been reported. We present a case of acute atrial fibrillation, with a rapid ventricular rate, successfully treated with intravenous amiodarone, in a 62-year-old man with dengue hemorrhagic fever, who had no structural heart disease.

  4. Potassium channel gene mutations rarely cause atrial fibrillation

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    Nam Edwin G

    2006-08-01

    Full Text Available Abstract Background Mutations in several potassium channel subunits have been associated with rare forms of atrial fibrillation. In order to explore the role of potassium channels in inherited typical forms of the arrhythmia, we have screened a cohort of patients from a referral clinic for mutations in the channel subunit genes implicated in the arrhythmia. We sought to determine if mutations in KCNJ2 and KCNE1-5 are a common cause of atrial fibrillation. Methods Serial patients with lone atrial fibrillation or atrial fibrillation with hypertension were enrolled between June 1, 2001 and January 6, 2005. Each patient underwent a standardized interview and physical examination. An electrocardiogram, echocardiogram and blood sample for genetic analysis were also obtained. Patients with a family history of AF were screened for mutations in KCNJ2 and KCNE1-5 using automated sequencing. Results 96 patients with familial atrial fibrillation were enrolled. Eighty-three patients had lone atrial fibrillation and 13 had atrial fibrillation and hypertension. Patients had a mean age of 56 years at enrollment and 46 years at onset of atrial fibrillation. Eighty-one percent of patients had paroxysmal atrial fibrillation at enrollment. Unlike patients with an activating mutation in KCNQ1, the patients had a normal QTc interval with a mean of 412 ± 42 ms. Echocardiography revealed a normal mean ejection fraction of 62.0 ± 7.2 % and mean left atrial dimension of 39.9 ± 7.0 mm. A number of common polymorphisms in KCNJ2 and KCNE1-5 were identified, but no mutations were detected. Conclusion Mutations in KCNJ2 and KCNE1-5 rarely cause typical atrial fibrillation in a referral clinic population.

  5. Recent advances in the molecular pathophysiology of atrial fibrillation

    Science.gov (United States)

    Wakili, Reza; Voigt, Niels; Kääb, Stefan; Dobrev, Dobromir; Nattel, Stanley

    2011-01-01

    Atrial fibrillation (AF) is an extremely common cardiac rhythm disorder that causes substantial morbidity and contributes to mortality. The mechanisms underlying AF are complex, involving both increased spontaneous ectopic firing of atrial cells and impulse reentry through atrial tissue. Over the past ten years, there has been enormous progress in understanding the underlying molecular pathobiology. This article reviews the basic mechanisms and molecular processes causing AF. We discuss the ways in which cardiac disease states, extracardiac factors, and abnormal genetic control lead to the arrhythmia. We conclude with a discussion of the potential therapeutic implications that might arise from an improved mechanistic understanding. PMID:21804195

  6. Reduced incidence of cardiac arrhythmias in walkers and runners.

    Directory of Open Access Journals (Sweden)

    Paul T Williams

    Full Text Available Walking is purported to reduce the risk of atrial fibrillation by 48%, whereas jogging is purported to increase its risk by 53%, suggesting a strong anti-arrhythmic benefit of walking over running. The purpose of these analyses is to compare incident self-reported physician-diagnosed cardiac arrhythmia to baseline energy expenditure (metabolic equivalent hours per day, METhr/d from walking, running and other exercise.Proportional hazards analysis of 14,734 walkers and 32,073 runners.There were 1,060 incident cardiac arrhythmias (412 walkers, 648 runners during 6.2 years of follow-up. The risk for incident cardiac arrhythmias declined 4.4% per baseline METhr/d walked by the walkers, or running in the runners (P = 0.0001. Specifically, the risk declined 14.2% (hazard ratio: 0.858 for 1.8 to 3.6 METhr/d, 26.5% for 3.6 to 5.4 METhr/d, and 31.7% for ≥5.4 METhr/d, relative to <1.8 METhr/d. The risk reduction per METhr/d was significantly greater for walking than running (P<0.01, but only because walkers were at 34% greater risk than runners who fell below contemporary physical activity guideline recommendations; otherwise the walkers and runners had similar risks for cardiac arrhythmias. Cardiac arrhythmias were unrelated to walking and running intensity, and unrelated to marathon participation and performance.The risk for cardiac arrhythmias was similar in walkers and runners who expended comparable METhr/d during structured exercise. We found no significant risk increase for self-reported cardiac arrhythmias associated with running distance, exercise intensity, or marathon participation. Rhythm abnormalities were based on self-report, precluding definitive categorization of the nature of the rhythm disturbance. However, even if the runners' arrhythmias include sinus bradycardia due to running itself, there was no increase in arrhythmias with greater running distance.

  7. Ventricular arrhythmias in Chagas disease

    Directory of Open Access Journals (Sweden)

    Marco Paulo Tomaz Barbosa

    2015-02-01

    Full Text Available Sudden death is one of the most characteristic phenomena of Chagas disease, and approximately one-third of infected patients develop life-threatening heart disease, including malignant ventricular arrhythmias. Fibrotic lesions secondary to chronic cardiomyopathy produce arrhythmogenic substrates that lead to the appearance and maintenance of ventricular arrhythmias. The objective of this study is to discuss the main clinical and epidemiological aspects of ventricular arrhythmias in Chagas disease, the specific workups and treatments for these abnormalities, and the breakthroughs needed to determine a more effective approach to these arrhythmias. A literature review was performed via a search of the PubMed database from 1965 to May 31, 2014 for studies of patients with Chagas disease. Clinical management of patients with chronic Chagas disease begins with proper clinical stratification and the identification of individuals at a higher risk of sudden cardiac death. Once a patient develops malignant ventricular arrhythmia, the therapeutic approach aims to prevent the recurrence of arrhythmias and sudden cardiac death by the use of implantable cardioverter defibrillators, antiarrhythmic drugs, or both. In select cases, invasive ablation of the reentrant circuit causing tachycardia may be useful. Ventricular arrhythmias are important manifestations of Chagas cardiomyopathy. This review highlights the absence of high-quality evidence regarding the treatment of ventricular arrhythmias in Chagas disease. Recognizing high-risk patients who require specific therapies, especially invasive procedures such as the implantation of cardioverter defibrillators and ablative approaches, is a major challenge in clinical practice.

  8. Arrhythmias in adult congenital heart disease: the year in review.

    Science.gov (United States)

    Mondésert, Blandine; Abadir, Sylvia; Khairy, Paul

    2013-05-01

    Management of arrhythmias is an integral component of care for adults with congenital heart disease (CHD). Our objective was to highlight the important advances from the year 2012 regarding arrhythmias in adult CHD, with a focus on diagnostic considerations, acute management, catheter ablation, and device therapy. During the course of 2012, Holter studies suggested that routine screening was helpful in guiding the clinical decisions for certain patient subgroups, such as adults with tetralogy of Fallot. Supportive evidence was provided for the common practice of anticoagulation and/or screening for intracardiac thrombosis by transesophageal echocardiography prior to electrically cardioverting atrial tachyarrhythmias. Advances in catheter ablation, particularly robotic magnetic navigation, offer new hope for patients in whom access to arrhythmia substrates is not feasible by standard means. The subcutaneous defibrillator emerged as an innovative solution of great interest to the patients at risk of sudden death in whom transvenous lead implantation is unachievable or contraindicated. Finally, 2012 ended with a major milestone: the establishment of physician certification in adult CHD by the American Board of Medical Specialties. The year 2012 witnessed important advances in the diagnosis and management of arrhythmias in adults with CHD.

  9. Ablative Radiotherapy as a Noninvasive Alternative to Catheter Ablation for Cardiac Arrhythmias.

    Science.gov (United States)

    Zei, Paul C; Soltys, Scott

    2017-09-01

    Stereotactic radioablation is a commonly utilized technology to noninvasively treat solid tumors with precision and efficacy. Using a robotic arm mounted delivery system, multiple low-dose ionizing radiation beams are delivered from multiple angles, concentrating ablative energy at the target tissue. Recently, this technology has been evaluated for treatment of cardiac arrhythmias. This review will present the basic underlying principles, proof-of-principle studies, and clinical experience with stereotactic arrhythmia radioablation. Most recently, stereotactic radioablation has been used to safely and effectively treat a limited number of patients with malignant arrhythmias, including ventricular tachycardia (VT) and atrial fibrillation (AF). Treatment protocols, outcomes, ongoing studies, and future directions will be discussed. Stereotactic radioablation is a well-established technology that has been shown to be a safe and effective therapy for patients with drug-refractory cardiac arrhythmias, including VT and AF. Further clinical evaluation to define safety and efficacy in larger populations of patients is needed.

  10. Impact of Fontan conversion with arrhythmia surgery and pacemaker therapy.

    Science.gov (United States)

    Hiramatsu, Takeshi; Iwata, Yusuke; Matsumura, Goki; Konuma, Takeshi; Yamazaki, Kenji

    2011-10-01

    In the long-term period after Fontan operation, atrial arrhythmia was one of the important factors to decide the postoperative quality of life. We reviewed the impact of Fontan conversion with arrhythmia surgery and pacemaker therapy. Thirty-eight patients underwent Fontan conversion using extracardiac conduit from 1992, and 22 patients with atrial arrhythmia underwent maze procedure simultaneously using cryoablation or radiofrequency ablation and epicardial DDD pacemaker implantation and 16 patients had regular 'sinus' rhythm before Fontan conversion. Mean follow-up period was 52 months. Pre- and postoperative clinical course were analyzed. Average weight, age at Fontan conversion, and years after first Fontan operation were 49.0 kg, 25.8 years old, 14.7 years, respectively. Nineteen percent of patients were in New York Heart Association class I (NYHA I), and 74% of patients were in NYHA II, and 7% were in NYHA III, respectively. Except three early deaths, actual survival rate at 1 year and 5 years were 80% and 64%, respectively. In survivors, 80% of the patients obtained regular heart rhythm including artificial pacemaker rhythm, although only 43% of the patients had regular 'sinus' rhythm before the Fontan conversion. Postoperative average cardiothoracic ratio and oxygen saturation (SpO(2)) were 50% and 94%, and 74% of patients were in NYHA I and 26% were in NYHA II, respectively, after Fontan conversion. Mid-term results of Fontan conversion with arrhythmia surgery and pacemaker therapy were acceptable. Restoration of regular rhythm might improve the postoperative NYHA status and the activity of the daily life. Copyright © 2011 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

  11. Simulation of Cardiac Arrhythmias Using a 2D Heterogeneous Whole Heart Model.

    Science.gov (United States)

    Balakrishnan, Minimol; Chakravarthy, V Srinivasa; Guhathakurta, Soma

    2015-01-01

    Simulation studies of cardiac arrhythmias at the whole heart level with electrocardiogram (ECG) gives an understanding of how the underlying cell and tissue level changes manifest as rhythm disturbances in the ECG. We present a 2D whole heart model (WHM2D) which can accommodate variations at the cellular level and can generate the ECG waveform. It is shown that, by varying cellular-level parameters like the gap junction conductance (GJC), excitability, action potential duration (APD) and frequency of oscillations of the auto-rhythmic cell in WHM2D a large variety of cardiac arrhythmias can be generated including sinus tachycardia, sinus bradycardia, sinus arrhythmia, sinus pause, junctional rhythm, Wolf Parkinson White syndrome and all types of AV conduction blocks. WHM2D includes key components of the electrical conduction system of the heart like the SA (Sino atrial) node cells, fast conducting intranodal pathways, slow conducting atriovenctricular (AV) node, bundle of His cells, Purkinje network, atrial, and ventricular myocardial cells. SA nodal cells, AV nodal cells, bundle of His cells, and Purkinje cells are represented by the Fitzhugh-Nagumo (FN) model which is a reduced model of the Hodgkin-Huxley neuron model. The atrial and ventricular myocardial cells are modeled by the Aliev-Panfilov (AP) two-variable model proposed for cardiac excitation. WHM2D can prove to be a valuable clinical tool for understanding cardiac arrhythmias.

  12. Online cardiac arrhythmia classification by means of circle maps analysis implemented on an intelligent miniaturized sensor.

    Science.gov (United States)

    Schiek, Michael; Schlösser, Mario; Schnitzer, Andreas; Ying, Hong

    2008-01-01

    The intermittent occurrence of cardiac arrhythmias like e.g. atrial fibrillation hampers their diagnosis and hence the treatment. Since persons suffering from atrial fibrillation are known to have a remarkable increased risk of stroke the diagnosis of atrial fibrillation is a matter of great importance. Easy and comfortable to use long term ECG recording systems capable of online arrhythmia classification might help to solve this problem. We developed an intelligent, miniaturized, and wireless networking sensor which allows lossless local data recordings up to 4 GB. With its outer dimensions of 20mm per rim and less than 15g of weight including the Lithium-Ion battery our modular designed sensor node is thoroughly capable of up to eight channel recordings with 8 kHz sample rate each and provides sufficient computational power for online digital signal processing. For online arrhythmia classification we will record one ECG channel and 3-axis accelerometer data with 512 Hz each, the later being used for activity classification based artifact identification. We adapted our recently developed circle maps analysis of short term heart rate variation to run on this miniaturized intelligent sensor powered by the Texas Instruments MSP430 microcontroller derivate F1611. With this configuration we started to evaluate the cardiac arrhythmia classification in long term ECG recordings.

  13. Arrhythmia Diagnosis Following an ICD Shock: Comment

    Directory of Open Access Journals (Sweden)

    Pual A. Levine

    2002-01-01

    ventricular tachycardia. Given the complexity of these patients, if atrial fibrillation was hemodynamically compromising, it might be appropriate to not enable any discrimination algorithms. Dr. John indicates that amiodarone was not tolerated and other drugs have both a higher incidence of side effects and lower efficacy rate. If the episodes of atrial fibrillation were not frequent, another option would be to allow the AF to trigger ATP therapy which was arrhythmogenic but then take advantage of the subsequent shock to not only terminated the induced-VT but also terminate the atrial fibrillation as occurred in this case.

  14. Electrophysiological Features of Atrial Flutter in Cardiac Sarcoidosis: A Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Narayanan Namboodiri, MD

    2012-11-01

    Full Text Available We report two cases of systemic sarcoidosis with atrial flutter as the clinical manifestation. In one patient, who had symptoms of shorter duration, the arrhythmia was no longer inducible after a course of glucocorticoid therapy. Electroanatomical mapping in the other case revealed patchy fibrosis of the left atrial myocardium and multiple macro-reentrant circuits. Sinus rhythm could be restored with ablation of these reentrant circuits. To our knowledge, this is the first report on the demonstration of atrial scarring in a patient with sarcoidosis using 3-D electroanatomical mapping. These two cases illustrate that the inflammation of atrial myocardium is the primary mechanism of atrial arrhythmias in patients with cardiac sarcoidosis.

  15. Structural and functional characteristics of myocard in patients with different forms of atrial fibrillation

    Directory of Open Access Journals (Sweden)

    L. I. Vasilyeva

    2015-02-01

    Full Text Available Aim. To study structural and functional characteristics of myocard in patients with different forms of atrial fibrillation. Atrial fibrillation is the most prevalent arrhythmia in clinical practice. Atrial fibrillation is a progressive disease: the duration of paroxysms increases over time and paroxysmal atrial fibrillation transforms to persistent, the last one becomes refractory to pharmacological and electrical cardioversion in time and transforms to permanent. So assessment of myocardial remodeling in patients with persistent and permanent atrial fibrillation is very actual. Methods and results. According to the aim of the study 133 patients with persistent atrial fibrillation and 100 patients with permanent atrial fibrillation were included into the study. Echocardiographic parameters of left and right atria function were studied. Conclusion. It was found that patients with persistent and permanent atrial fibrillation are characterized with both left and right atrias remodeling. Remodeling of the atrias is less pronounced in patients with permanent atrial fibrillation in comparison with persistent atrial fibrillation patients and arrhythmia recurrence.

  16. Atrial Fibrillation

    Science.gov (United States)

    ... A-Z Clinical Trials Publications and Resources Health Education and Awareness The Science Science Home Blood Disorders ... heart's two upper chambers—called the atria (AY-tree-uh)—to fibrillate. The ... a difficult decision concerning surgery for patients with atrial fibrillation, the ...

  17. Arrhythmia Evaluation in Wearable ECG Devices

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    Muammar Sadrawi

    2017-10-01

    Full Text Available This study evaluates four databases from PhysioNet: The American Heart Association database (AHADB, Creighton University Ventricular Tachyarrhythmia database (CUDB, MIT-BIH Arrhythmia database (MITDB, and MIT-BIH Noise Stress Test database (NSTDB. The ANSI/AAMI EC57:2012 is used for the evaluation of the algorithms for the supraventricular ectopic beat (SVEB, ventricular ectopic beat (VEB, atrial fibrillation (AF, and ventricular fibrillation (VF via the evaluation of the sensitivity, positive predictivity and false positive rate. Sample entropy, fast Fourier transform (FFT, and multilayer perceptron neural network with backpropagation training algorithm are selected for the integrated detection algorithms. For this study, the result for SVEB has some improvements compared to a previous study that also utilized ANSI/AAMI EC57. In further, VEB sensitivity and positive predictivity gross evaluations have greater than 80%, except for the positive predictivity of the NSTDB database. For AF gross evaluation of MITDB database, the results show very good classification, excluding the episode sensitivity. In advanced, for VF gross evaluation, the episode sensitivity and positive predictivity for the AHADB, MITDB, and CUDB, have greater than 80%, except for MITDB episode positive predictivity, which is 75%. The achieved results show that the proposed integrated SVEB, VEB, AF, and VF detection algorithm has an accurate classification according to ANSI/AAMI EC57:2012. In conclusion, the proposed integrated detection algorithm can achieve good accuracy in comparison with other previous studies. Furthermore, more advanced algorithms and hardware devices should be performed in future for arrhythmia detection and evaluation.

  18. Clinical Profile of Cardiac Arrhythmias in Children Attending the Out Patient Department of a Tertiary Paediatric Care Centre in Chennai.

    Science.gov (United States)

    Premkumar, Sarala; Sundararajan, Premkumar; Sangaralingam, Thangavelu

    2016-12-01

    The presentation of symptoms of paediatric arrhythmias vary depending on the age and underlying heart disease. Physical examination of children with important arrhythmias may be entirely normal. Aim is to study the characteristics of cardiac arrhythmias in paediatric patients in a tertiary paediatric care centre in Chennai, India. The participants (n=60) were from birth to 12 years of age. Patients with sinus arrhythmias, sinus tachycardia and sinus bradycardia were excluded. Proportions of various parameters of interest like clinical features, age and sex distribution and underlying heart disease of children presenting with cardiac arrhythmias were arrived. Statistical analysis was performed using SPSS version 16.0. Ventricular ectopics were the most common type of arrhythmias observed in the present study followed by Sinus Node Dysfunction (SND). The most common type of SND was sino atrial arrest. Supra ventricular tachycardia was the most frequently sustained tachyarrhythmia in the present study. An increased association of WPW (Wolf Parkinson White Syndrome) with specific congenital cardiac defects was noted. Cardiac arrhythmias in children can present at anytime from fetal life to adolescence and their recognition requires high index of suspicion. While majority of children with arrhythmias have structurally normal heart, they are frequently encountered in children with underlying heart disease. Treatment of paediatric arrhythmias should be guided by the severity of the patient, the structure and function of the heart.

  19. 3D X-ray imaging methods in support catheter ablations of cardiac arrhythmias.

    Science.gov (United States)

    Stárek, Zdeněk; Lehar, František; Jež, Jiří; Wolf, Jiří; Novák, Miroslav

    2014-10-01

    Cardiac arrhythmias are a very frequent illness. Pharmacotherapy is not very effective in persistent arrhythmias and brings along a number of risks. Catheter ablation has became an effective and curative treatment method over the past 20 years. To support complex arrhythmia ablations, the 3D X-ray cardiac cavities imaging is used, most frequently the 3D reconstruction of CT images. The 3D cardiac rotational angiography (3DRA) represents a modern method enabling to create CT like 3D images on a standard X-ray machine equipped with special software. Its advantage lies in the possibility to obtain images during the procedure, decreased radiation dose and reduction of amount of the contrast agent. The left atrium model is the one most frequently used for complex atrial arrhythmia ablations, particularly for atrial fibrillation. CT data allow for creation and segmentation of 3D models of all cardiac cavities. Recently, a research has been made proving the use of 3DRA to create 3D models of other cardiac (right ventricle, left ventricle, aorta) and non-cardiac structures (oesophagus). They can be used during catheter ablation of complex arrhythmias to improve orientation during the construction of 3D electroanatomic maps, directly fused with 3D electroanatomic systems and/or fused with fluoroscopy. An intensive development in the 3D model creation and use has taken place over the past years and they became routinely used during catheter ablations of arrhythmias, mainly atrial fibrillation ablation procedures. Further development may be anticipated in the future in both the creation and use of these models.

  20. Postoperative Arrhythmias after Cardiac Surgery: Incidence, Risk Factors, and Therapeutic Management

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    Giovanni Peretto

    2014-01-01

    Full Text Available Arrhythmias are a known complication after cardiac surgery and represent a major cause of morbidity, increased length of hospital stay, and economic costs. However, little is known about incidence, risk factors, and treatment of early postoperative arrhythmias. Both tachyarrhythmias and bradyarrhythmias can present in the postoperative period. In this setting, atrial fibrillation is the most common heart rhythm disorder. Postoperative atrial fibrillation is often self-limiting, but it may require anticoagulation therapy and either a rate or rhythm control strategy. However, ventricular arrhythmias and conduction disturbances can also occur. Sustained ventricular arrhythmias in the recovery period after cardiac surgery may warrant acute treatment and long-term preventive strategy in the absence of reversible causes. Transient bradyarrhythmias may be managed with temporary pacing wires placed at surgery, but significant and persistent atrioventricular block or sinus node dysfunction can occur with the need for permanent pacing. We provide a complete and updated review about mechanisms, risk factors, and treatment strategies for the main postoperative arrhythmias.

  1. In Search of Hidden Arrhythmia

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    Johnson Francis

    2015-10-01

    Full Text Available Cardiac rhythm disorders could be very common and minimal significance like isolated ventricular ectopics are very serious and life threatening like ventricular tachycardia or fibrillation. Often it is an irregular pulse or heart beats which calls our attention to the presence of cardiac rhythm disorders. But many times, cardiac arrhythmia is intermittent and not manifest at the time of physical examination. A simple 12 lead electrocardiogram with a long rhythm strip can document cardiac arrhythmia which is frequent, but often fails to record intermittent arrhythmia which can still be quite symptomatic and sometimes life threatenting. This brief review is on the various modalities of electrocardiographic recordings used for documenting arrhythmia which is not easily documented by a 12 lead electrocardiogram with a long rhythm strip.

  2. Management of Newly Diagnosed Atrial Fibrillation in an Outpatient Clinic Setting

    DEFF Research Database (Denmark)

    Thrysoee, Lars; Strömberg, Anna; Brandes, Axel

    2018-01-01

    AIMS: To gain in-depth knowledge of patients' experiences of the consultation processes at a multidisciplinary atrial fibrillation outpatient clinic in a university hospital in Denmark. BACKGROUND: Atrial fibrillation is the most common cardiac arrhythmia associated with morbidity and mortality...... on what AF was before as well as after their consultation. The communication was concentrated on the medical aspects of atrial fibrillation and visiting the clinic was an overwhelming experience for the patients. They had difficulty understanding what atrial fibrillation was, why they were treated...

  3. Pediatric giant right atrial aneurysm: a case series and review of the literature.

    Science.gov (United States)

    Harder, Erika E; Ohye, Richard G; Knepp, Marc D; Owens, Sonal T

    2014-01-01

    Giant right atrial aneurysm is a rare form of congenital heart disease with a wide spectrum of clinical presentation varying from asymptomatic patients to those with refractory atrial arrhythmias or severe airway obstruction. Diagnosis is often confused with other causes of right atrial dilation such as Ebstein disease. Because of its rare occurrence and variable clinical presentation, inconsistencies in medical and surgical management strategies exist between centers. We present five cases of giant right atrial aneurysm managed at our institution and discuss the clinical presentation, diagnostic challenges, and medical and surgical management. © 2013 Wiley Periodicals, Inc.

  4. Calcium Signaling and Cardiac Arrhythmias.

    Science.gov (United States)

    Landstrom, Andrew P; Dobrev, Dobromir; Wehrens, Xander H T

    2017-06-09

    There has been a significant progress in our understanding of the molecular mechanisms by which calcium (Ca2+) ions mediate various types of cardiac arrhythmias. A growing list of inherited gene defects can cause potentially lethal cardiac arrhythmia syndromes, including catecholaminergic polymorphic ventricular tachycardia, congenital long QT syndrome, and hypertrophic cardiomyopathy. In addition, acquired deficits of multiple Ca2+-handling proteins can contribute to the pathogenesis of arrhythmias in patients with various types of heart disease. In this review article, we will first review the key role of Ca2+ in normal cardiac function-in particular, excitation-contraction coupling and normal electric rhythms. The functional involvement of Ca2+ in distinct arrhythmia mechanisms will be discussed, followed by various inherited arrhythmia syndromes caused by mutations in Ca2+-handling proteins. Finally, we will discuss how changes in the expression of regulation of Ca2+ channels and transporters can cause acquired arrhythmias, and how these mechanisms might be targeted for therapeutic purposes. © 2017 American Heart Association, Inc.

  5. Data analysis in cardiac arrhythmias.

    Science.gov (United States)

    Rodrigo, Miguel; Pedrón-Torecilla, Jorge; Hernández, Ismael; Liberos, Alejandro; Climent, Andreu M; Guillem, María S

    2015-01-01

    Cardiac arrhythmias are an increasingly present in developed countries and represent a major health and economic burden. The occurrence of cardiac arrhythmias is closely linked to the electrical function of the heart. Consequently, the analysis of the electrical signal generated by the heart tissue, either recorded invasively or noninvasively, provides valuable information for the study of cardiac arrhythmias. In this chapter, novel cardiac signal analysis techniques that allow the study and diagnosis of cardiac arrhythmias are described, with emphasis on cardiac mapping which allows for spatiotemporal analysis of cardiac signals.Cardiac mapping can serve as a diagnostic tool by recording cardiac signals either in close contact to the heart tissue or noninvasively from the body surface, and allows the identification of cardiac sites responsible of the development or maintenance of arrhythmias. Cardiac mapping can also be used for research in cardiac arrhythmias in order to understand their mechanisms. For this purpose, both synthetic signals generated by computer simulations and animal experimental models allow for more controlled physiological conditions and complete access to the organ.

  6. Granger Causality and Jensen–Shannon Divergence to Determine Dominant Atrial Area in Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Raquel Cervigón

    2018-01-01

    Full Text Available Atrial fibrillation (AF is already the most commonly occurring arrhythmia. Catheter pulmonary vein ablation has emerged as a treatment that is able to make the arrhythmia disappear; nevertheless, recurrence to arrhythmia is very frequent. In this study, it is proposed to perform an analysis of the electrical signals recorded from bipolar catheters at three locations, pulmonary veins and the right and left atria, before to and during the ablation procedure. Principal Component Analysis (PCA was applied to reduce data dimension and Granger causality and divergence techniques were applied to analyse connectivity along the atria, in three main regions: pulmonary veins, left atrium (LA and right atrium (RA. The results showed that, before the procedure, patients with recurrence in the arrhythmia had greater connectivity between atrial areas. Moreover, during the ablation procedure, in patients with recurrence in the arrhythmial both atria were more connected than in patients that maintained sinus rhythms. These results can be helpful for procedures designing to end AF.

  7. Role of neural modulation in the pathophysiology of atrial fibrillation

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    Shailesh Male

    2014-01-01

    Full Text Available Atrial-fibrillation (AF is the most common clinically encountered arrhythmia affecting over 1 per cent of population in the United States and its prevalence seems to be moving only in forward direction. A recent systemic review estimates global prevalence of AF to be 596.2 and 373.1 per 100,000 population in males and females respectively. Multiple mechanisms have been put forward in the pathogenesis of AF, however; multiple wavelet hypothesis is the most accepted theory so far. Similar to the conduction system of the heart, a neural network exists which surrounds the heart and plays an important role in formation of the substrate of AF and when a trigger is originated, usually from pulmonary vein sleeves, AF occurs. This neural network includes ganglionated plexi (GP located adjacent to pulmonary vein ostia which are under control of higher centers in normal people. When these GP become hyperactive owing to loss of inhibition from higher centers e.g. in elderly, AF can occur. We can control these hyperactive GP either by stimulating higher centers and their connections, e.g. vagus nerve stimulation or simply by ablating these GP. This review provides detailed information about the different proposed mechanisms underlying AF, the exact role of autonomic neural tone in the pathogenesis of AF and the possible role of neural modulation in the treatment of AF.

  8. [Anti-arrhythmia efficacy of propafenone in children. Apropos of 30 cases].

    Science.gov (United States)

    Lucet, V; Do Ngoc, D; Fidelle, J; Sidi, D; Batisse, A; Loth, P; Vrancea, F; Villain, E; Coumel, P

    1987-08-01

    Thirty children aged from 3 months to 20 years were treated with propafenone 250 to 650 mg/m2 divided into 2 to 4 daily doses, for a mean period of 14 months (range: 4 days to 5 years); 8 had chronic atrial tachycardia, 9 had junctional arrhythmia and 13 had ventricular arrhythmia. There were 17 good results (suppression of the arrhythmia), 7 fair results (good clinical effect but partial persistence of the arrhythmia) and 6 failures, either because the drug proved ineffective (3 cases) or on account of side-effects (3 cases). In the treatment of chronic atrial tachycardia propafenone seemed to be more effective than amiodarone in 3 cases and as effective as that drug in 2 cases. In junctional arrhythmia propafenone was certainly effective but unpredictably so (3 good results, 2 fair results, 4 failures). Among ventricular arrhythmias, ventricular tachycardia in bursts was the one which benefited most regularly from treatment with propafenone: the results in 8 patients were better than those obtained with other antiarrhythmic agents (class I drugs, beta-blockers, calcium antagonists); only amiodarone proved superior to propafenone in this type of arrhythmia. Despite a 27% incidence of side-effects, propafenone was generally well tolerated by the children, with no significant gastrointestinal disorders. No depressive effect on the myocardium was noted in 6 children with moderate heart failure well controlled by digitalis and diuretics. However, since overdosage may cause severe disorders of conduction with widened ventriculogram, we recommend regular ECG monitoring during the first 3 days of treatment at least: although there is little slowing down of sinus rate (12%) and little modification of the slow phase under treatment, serious toxicity is possible. Thus, propafenone is a drug that should be handled with caution, but it constitutes a major addition to the range of antiarrhythmic agents which can be used in paediatrics.

  9. Left atrial appendage closure devices for cardiovascular risk reduction in atrial fibrillation patients

    Directory of Open Access Journals (Sweden)

    Cruz-Gonzalez I

    2015-05-01

    Full Text Available Ignacio Cruz-Gonzalez,* Juan Carlos Rama-Merchan,* Javier Rodriguez-Collado, Javier Martin-Moreiras, Alejandro Diego-Nieto, Antonio Arribas-Jimenez, Pedro Luís SanchezDepartment of Cardiology, University Hospital of Cardiology and IBSAL, Salamanca, Spain *Ignacio Cruz-Gonzalez and Juan Carlos Rama-Merchan have contributed equally to this work and should be considered co-first authors Abstract: Atrial fibrillation (AF is the most common sustained arrhythmia in clinical practice. AF is associated with a 4–5-fold increased risk of stroke and systemic embolism. Oral anticoagulant is the first-line therapy for this purpose, but it has various limitations and is often contraindicated or underutilized. Autopsy and surgical data have suggested that 90% of atrial thrombi in nonvalvular AF patients originate from the left atrial appendage, leading to the development of percutaneous closure for thromboembolic prevention. This paper examines the current evidence on left atrial appendage closure devices for cardiovascular risk reduction in AF patients. Keywords: atrial fibrillation, left atrial appendage, stroke, oral anticoagulant, percutaneous closure, thromboembolic prevention

  10. Left atrial function in heart failure with impaired and preserved ejection fraction.

    Science.gov (United States)

    Fang, Fang; Lee, Alex Pui-Wai; Yu, Cheuk-Man

    2014-09-01

    Left atrial structural and functional changes in heart failure are relatively ignored parts of cardiac assessment. This review illustrates the pathophysiological and functional changes in left atrium in heart failure as well as their prognostic value. Heart failure can be divided into those with systolic dysfunction and heart failure with preserved ejection fraction (HFPEF). Left atrial enlargement and dysfunction commonly occur in systolic heart failure, in particular, in idiopathic dilated cardiomyopathy. Atrial enlargement and dysfunction also carry important prognostic value in systolic heart failure, independently of known parameters such as left ventricular ejection fraction. In HFPEF, there is evidence of left atrial enlargement, impaired atrial compliance, and reduction of atrial pump function. This occurs not only at rest but also during exercise, indicating significant impairment of atrial contractile reserve. Furthermore, atrial dyssynchrony is common in HFPEF. These factors further contribute to the development of new onset or progression of atrial arrhythmias, in particular, atrial fibrillation. Left atrial function is an integral part of cardiac function and its structural and functional changes in heart failure are common. As changes of left atrial structure and function have different clinical implications in systolic heart failure and HFPEF, routine assessment is warranted.

  11. Utility of the filtered bipolar esophageal lead in the diagnosis of arrhythmias.

    Science.gov (United States)

    Ishinaga, T; Komatsu, C

    1984-12-01

    Electrophysiologic study was performed in 25 patients with tachycardia or bradycardia attacks. The coronary sinus (CS) and filtered bipolar esophageal electrograms were recorded simultaneously to compare the phase of atrial activations. During sinus rhythm and high right atrial pacing, the esophageal and proximal CS atrial activations were nearly simultaneous but earlier by 26 +/- 5 msec on the average than the distal CS atrial activations. During reciprocating tachycardia due to reentry using a left-side accessory atrioventricular pathway for retrograde conduction the esophageal and CS atrial activations occurred earlier than the low septal right atrial activation, so the esophageal lead can be used as a substitute for the CS lead to clarify the eccentric retrograde atrial activation sequence. By using the filtered bipolar esophageal lead, the interval from Q wave on the surface electrocardiogram to the first rapid deflection in the esophageal atrial activation (Q-AESO interval) was measured in 15 patients with supra-ventricular tachycardia. All patients with reciprocating tachycardia due to reentry using a left side accessory atrioventricular pathway had Q-AESO intervals between 100 to 130 msec and four of five patients with a right side accessory atrioventricular pathway for retrograde conduction had Q-AESO intervals between 130 to 150 msec. In contrast, all patients with reentry in the atrioventricular node had Q-AESO intervals between 30 to 60 msec. The esophageal lead is also of value in the prompt diagnosis of atrial flutter and ventricular tachycardia, since the esophageal electrograms readily reveal the relationship between atrial and ventricular activations. In conclusion, the filtered bipolar esophageal lead provides a non-invasive method for the quick diagnosis of various arrhythmias.

  12. Atrial natriuretic peptide regulates adipose tissue accumulation in adult atria

    Science.gov (United States)

    Suffee, Nadine; Moore-Morris, Thomas; Farahmand, Patrick; Rücker-Martin, Catherine; Dilanian, Gilles; Fradet, Magali; Sawaki, Daigo; Derumeaux, Geneviève; LePrince, Pascal; Clément, Karine; Dugail, Isabelle; Puceat, Michel; Hatem, Stéphane N.

    2017-01-01

    The abundance of epicardial adipose tissue (EAT) is associated with atrial fibrillation (AF), the most frequent cardiac arrhythmia. However, both the origin and the factors involved in EAT expansion are unknown. Here, we found that adult human atrial epicardial cells were highly adipogenic through an epithelial–mesenchymal transition both in vitro and in vivo. In a genetic lineage tracing the WT1CreERT2+/−RosatdT+/− mouse model subjected to a high-fat diet, adipocytes of atrial EAT derived from a subset of epicardial progenitors. Atrial myocardium secretome induces the adipogenic differentiation of adult mesenchymal epicardium-derived cells by modulating the balance between mesenchymal Wingless-type Mouse Mammary Tumor Virus integration site family, member 10B (Wnt10b)/β-catenin and adipogenic ERK/MAPK signaling pathways. The adipogenic property of the atrial secretome was enhanced in AF patients. The atrial natriuretic peptide secreted by atrial myocytes is a major adipogenic factor operating at a low concentration by binding to its natriuretic peptide receptor A (NPRA) receptor and, in turn, by activating a cGMP-dependent pathway. Hence, our data indicate cross-talk between EAT expansion and mechanical function of the atrial myocardium. PMID:28096344

  13. Types of Arrhythmia in Children

    Science.gov (United States)

    ... common abnormal tachycardia in children is supraventricular tachycardia (SVT). It's also called paroxysmal atrial tachycardia (PAT) or ... episodes are prolonged or frequent. For many infants, SVT is a time-limited problem. Symptoms often stop, ...

  14. Arrhythmias after coronary bypass surgery.

    OpenAIRE

    Ormerod, O J; McGregor, C G; Stone, D L; Wisbey, C; Petch, M C

    1984-01-01

    Ninety patients undergoing coronary bypass surgery were studied prospectively by bedside and subsequent ambulatory electrocardiographic monitoring to investigate the incidence, possible causes, and prevention of atrial fibrillation. Patients with good left ventricular function were divided randomly into a control group or groups treated with digoxin or propranolol. In the control group the incidence of atrial fibrillation was 27% and of significant ventricular extrasystoles 3%. Propranolol re...

  15. Clinical Differences between Subtypes of Atrial Fibrillation and Flutter: Cross-Sectional Registry of 407 Patients

    Science.gov (United States)

    Almeida, Eduardo Dytz; Guimarães, Raphael Boesche; Stephan, Laura Siga; Medeiros, Alexandre Kreling; Foltz, Katia; Santanna, Roberto Tofani; Pires, Leonardo Martins; Kruse, Marcelo Lapa; de Lima, Gustavo Glotz; Leiria, Tiago Luiz Luz

    2015-01-01

    Introduction Atrial fibrillation and atrial flutter account for one third of hospitalizations due to arrhythmias, determining great social and economic impacts. In Brazil, data on hospital care of these patients is scarce. Objective To investigate the arrhythmia subtype of atrial fibrillation and flutter patients in the emergency setting and compare the clinical profile, thromboembolic risk and anticoagulants use. Methods Cross-sectional retrospective study, with data collection from medical records of every patient treated for atrial fibrillation and flutter in the emergency department of Instituto de Cardiologia do Rio Grande do Sul during the first trimester of 2012. Results We included 407 patients (356 had atrial fibrillation and 51 had flutter). Patients with paroxysmal atrial fibrillation were in average 5 years younger than those with persistent atrial fibrillation. Compared to paroxysmal atrial fibrillation patients, those with persistent atrial fibrillation and flutter had larger atrial diameter (48.6 ± 7.2 vs. 47.2 ± 6.2 vs. 42.3 ± 6.4; p < 0.01) and lower left ventricular ejection fraction (66.8 ± 11 vs. 53.9 ± 17 vs. 57.4 ± 16; p < 0.01). The prevalence of stroke and heart failure was higher in persistent atrial fibrillation and flutter patients. Those with paroxysmal atrial fibrillation and flutter had higher prevalence of CHADS2 score of zero when compared to those with persistent atrial fibrillation (27.8% vs. 18% vs. 4.9%; p < 0.01). The prevalence of anticoagulation in patients with CHA2DS2-Vasc ≤ 2 was 40%. Conclusions The population in our registry was similar in its comorbidities and demographic profile to those of North American and European registries. Despite the high thromboembolic risk, the use of anticoagulants was low, revealing difficulties for incorporating guideline recommendations. Public health strategies should be adopted in order to improve these rates. PMID:26016782

  16. Inflammation markers are associated with metabolic syndrome and ventricular arrhythmia in patients with coronary artery disease

    Directory of Open Access Journals (Sweden)

    Krzysztof Safranow

    2016-02-01

    previous studies have suggested that the inflammatory process plays an important role in generation of cardiac arrhythmia, but the majority of these reports concerned atrial fibrillation (AF [28]. These findings are supported by experimental studies, since atrial biopsies taken from patients with AF compared with controls have demonstrated evidence of inflammatory infiltrates and oxidative damage within the atrial tissue [10]. Inflammation and oxidative injury directly affect atrial myocyte contraction, electrical conduction, myocyte apoptosis, and cardiac fibrosis [39]. CRP can induce AF, causing the disarray of normal cell membrane structure by interaction with lysophospholipids followed by activation of the complement system and phagocytosis [35]. Our results did not show an association of AF with inflammation markers, but there were only 9 patients with AF in our study group. Similar mechanisms may be involved in the generation of ventricular arrhythmia. Moreover, inflammatory biomarkers can transform a stable atherosclerotic plaque into an unstable lesion, leading to ischemia-induced ventricular arrhythmias and sudden cardiac death events [40]. In the study of Albert et al., higher CRP levels were independently associated with an increased risk of sudden cardiac death over a 17-year follow-up period [2]. In another study, frequent premature ventricular contractions together with high CRP were associated with higher risk of death and acute myocardial infarction [50]. High peak serum CRP was an independent predictor of VT/VF in STEMI patients treated with primary percutaneous coronary intervention, while WBC was also significantly higher in patients with VT/VF [33]. High serum CRP was an independent predictor of VT/VF or cardiac death after ICD implantation [58]. In another study, increased CRP was an independent predictor of VT in ICD recipients after myocardial infarction [7]. Elevated preimplantation hs-CRP serum level was independently associated with increased

  17. Characterization of Complex Fractionated Atrial Electrograms by Sample Entropy: An International Multi-Center Study

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    Eva Cirugeda–Roldán

    2015-10-01

    Full Text Available Atrial fibrillation (AF is the most commonly clinically-encountered arrhythmia. Catheter ablation of AF is mainly based on trigger elimination and modification of the AF substrate. Substrate mapping ablation of complex fractionated atrial electrograms (CFAEs has emerged to be a promising technique. To improve substrate mapping based on CFAE analysis, automatic detection algorithms need to be developed in order to simplify and accelerate the ablation procedures. According to the latest studies, the level of fractionation has been shown to be promisingly well estimated from CFAE measured during radio frequency (RF ablation of AF. The nature of CFAE is generally nonlinear and nonstationary, so the use of complexity measures is considered to be the appropriate technique for the analysis of AF records. This work proposes the use of sample entropy (SampEn, not only as a way to discern between non-fractionated and fractionated atrial electrograms (A-EGM, Entropy 2015, 17 7494 but also as a tool for characterizing the degree of A-EGM regularity, which is linked to changes in the AF substrate and to heart tissue damage. The use of SampEn combined with a blind parameter estimation optimization process enables the classification between CFAE and non-CFAE with statistical significance (p < 0:001, 0.89 area under the ROC, 86% specificity and 77% sensitivity over a mixed database of A-EGM combined from two independent CFAE signal databases, recorded during RF ablation of AF in two EU countries (542 signals in total. On the basis of the results obtained in this study, it can be suggested that the use of SampEn is suitable for real-time support during navigation of RF ablation of AF, as only 1.5 seconds of signal segments need to be analyzed.

  18. Small-conductance Ca2+ -activated K+ channels and cardiac arrhythmias.

    Science.gov (United States)

    Zhang, Xiao-Dong; Lieu, Deborah K; Chiamvimonvat, Nipavan

    2015-08-01

    Small-conductance Ca2+ -activated K+ (SK, KCa2) channels are unique in that they are gated solely by changes in intracellular Ca2+ and, hence, function to integrate intracellular Ca2+ and membrane potentials on a beat-to-beat basis. Recent studies have provided evidence for the existence and functional significance of SK channels in the heart. Indeed, our knowledge of cardiac SK channels has been greatly expanded over the past decade. Interests in cardiac SK channels are further driven by recent studies suggesting the critical roles of SK channels in human atrial fibrillation, the SK channel as a possible novel therapeutic target in atrial arrhythmias, and upregulation of SK channels in heart failure in animal models and in human heart failure. However, there remain critical gaps in our knowledge. Specifically, blockade of SK channels in cardiac arrhythmias has been shown to be both antiarrhythmic and proarrhythmic. This contemporary review provides an overview of the literature on the role of cardiac SK channels in cardiac arrhythmias and serves as a discussion platform for the current clinical perspectives. At the translational level, development of SK channel blockers as a new therapeutic strategy in the treatment of atrial fibrillation and the possible proarrhythmic effects merit further considerations and investigations. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  19. Frequency of cardiac arrhythmias in high and low- yielding dairy cows

    Directory of Open Access Journals (Sweden)

    Afshin Jafari Dehkordi

    2014-06-01

    Full Text Available Electrocardiography (ECG may be used to recognize cardiac disorders. Levels of milk production may change the serum electrolytes which its imbalance has a role in cardiac arrhythmia. Fifty high yielding and fifty low yielding Holstein dairy cows were used in this study. Electrocardiography was recorded by base-apex lead and blood samples were collected from jugular vein for measurement of serum elements such as sodium, potassium, calcium, phosphorous, iron and magnesium. Cardiac dysrhythmias were detected more frequent in low yielding Holstein cows (62.00% compared to high yielding Holstein cows (46.00%. The cardiac dysrhythmias that were observed in low yielding Holstein cows included sinus arrhythmia (34.70%, wandering pacemaker (22.45 %, bradycardia (18.37%, tachycardia (10.20%, atrial premature beat (2.04%, sinoatrial block (2.04%, atrial fibrillation (8.16% and atrial tachycardia (2.04%. The cardiac dysrhythmias were observed in high yielding Holstein cows including, sinus arrhythmia (86.95% and wandering pacemaker (13.05%. Also, notched P wave was observed to be 30% and 14% in high- and low- yielding Holstein cows respectively. The serum calcium concentration of low yielding Holstein cows was significantly lower than that of high yielding Holstein cows. There was not any detectable significant difference in other serum elements between high- and low- yielding Holstein cows. Based on the result of present study, could be concluded that low serum concentration of calcium results to more frequent dysrhythmias in low yielding Holstein cows.

  20. Postoperative arrhythmias and myocardial electrolytes in patients undergoing coronary artery bypass grafting.

    Science.gov (United States)

    Jensen, B M; Alstrup, P; Klitgård, N A

    1996-01-01

    Electrolyte changes in right atrial and skeletal muscle pre- intra- and postoperatively, and their relationship to the development of postoperative atrial fibrillation or flutter were evaluated in 31 patients with coronary artery bypass grafting (CABG). Such postoperative arrhythmias occurred in 14 patients (45%). Before CABG the skeletal muscle potassium concentration was lower in these patients than in the others: median 261.4 (range 148.2-329.5) vs 298.6 (167.1-416.4) mumol/g dry weight, p = 0.017. The right atrial potassium concentration was normal, but sodium levels were higher in the patients with, than in those without postoperative arrhythmias: median 340.3 (263.7-454.9) vs 296.3 (203.9-355.0) mumol/g dry weight, p = 0.008, indicating disturbed transmembrane electrolyte transfer. During CABG the potassium levels fell and sodium increased in both right atrium and skeletal muscle, and on postoperative day 2 the potassium content in skeletal muscle was not yet restored. Magnesium levels showed no changes in right atrium or skeletal muscle, but serum magnesium declined postoperatively. As the observed electrolyte derangements may be important in the development of postoperative arrhythmias, concomitant potassium and magnesium supplement postoperatively may be beneficial in restoring cellular potassium concentration.

  1. THE PREVALENCE AND CLINICAL SIGNIFICANCE OF CARDIAC ARRHYTHMIAS

    Directory of Open Access Journals (Sweden)

    E. V. Zatonskaya

    2017-01-01

    Full Text Available Arrhythmias are one of the most complex, insufficiently studied, and therefore one of the most urgent problems of modern cardiology. A wide spectrum of clinical manifestations of cardiac rhythm disorders (CRDs, their detection both in various diseases and in healthy people, necessitate the study of their prevalence in populations. In the majority of conducted epidemiological studies a single recording of electrocardiogram (ECG was used. This is the most usable method for examination of large populations but a little informative for detecting arrhythmias. The small frequency of CRDs detected during ECG recording is due to the short duration of its registration. An increase in the duration of ECG recording (ECG recording for 2 minutes, continuous recording of 100 cardiocycles leads to an increase in arrhythmias frequency. With a wide introduction in the practice of ECG monitoring by Holter as well as the use of individual recorders of electrocardiogram ("handheld ECG recording" data appeared indicating a much higher frequency of CRDs. Data obtained in numerous studies on the prevalence of arrhythmias are very contradictory and depend both on the characteristics of populations and on methodological approaches, which requires further epidemiological studies. At the same time, the main initiating point of such researches is the clinical significance of certain CRDs. However, if the clinical significance of ventricular tachyarrhythmias and atrial fibrillation does not currently cause any doubt, the clinical significance of extrasystoles is highly controversial, despite the high their prevalence, including this in prognostically unfavorable groups of patients. In recent years, the results of a number of studies have been published that allow to think about the adverse effects of both supraventricular and ventricular extrasystoles of the course of certain cardiovascular diseases. Very heterogeneous results of the performed studies, as well as data about

  2. Atrial electromechanical cycle length mapping in paced canine hearts in vivo.

    Science.gov (United States)

    Costet, Alexandre; Bunting, Ethan; Grondin, Julien; Gambhir, Alok; Konofagou, Elisa E

    2015-07-01

    Atrial arrhythmias affect millions of people worldwide. Characterization and study of arrhythmias in the atria in the clinic is currently performed point by point using mapping catheters capable of generating maps of the electrical activation rate or cycle length. In this paper, we describe a new ultrasound-based mapping technique called electromechanical cycle length mapping (ECLM) capable of estimating the electromechanical activation rate, or cycle length, i.e., the rate of the mechanical activation of the myocardium which follows the electrical activation. ECLM relies on frequency analysis of the incremental strain within the atria and can be performed in a single acquisition. ECLM was validated in a canine model paced from the left atrial appendage, against pacing rates within the reported range of cycle lengths previously measured during atrial arrhythmias such as atrial fibrillation. Correlation between the global estimated electromechanical cycle lengths and pacing rates was shown to be excellent (slope = 0.983, intercept = 3.91, r(2) = 0.9999). The effect of the number of cardiac cycles on the performance of ECLM was also investigated and the reproducibility of ECLM was demonstrated (error between consecutive acquisitions for all pacing rates: 6.3 ± 4.3%). These findings indicate the potential of ECLM for noninvasively characterizing atrial arrhythmias and provide feedback on the treatment planning of catheter ablation procedures in the clinic.

  3. Features and costs of patients admitted for cardiac arrhythmias in Spain.

    Science.gov (United States)

    Montes-Santiago, J; Rodil, V; Formiga, F; Cepeda, J M; Urrutia, A

    2013-01-01

    Cardiac rhythm alterations are a frequent cause of hospital admission. However, we do not know their characteristics and economic costs. We have analyzed the epidemiology and cost of hospitalizations due to cardiac arrhythmias in the National Health System. The characteristics and costs were reviewed in patients admitted with a principal diagnosis of cardiac arrhythmia (1997-2010;diagnosis related groups [DRG] -138 and 139 of the National Health System minimum data base set). Atrial fibrillation/flutter accounted for 65% of these DRGs. The secondary diagnoses prevalent in such DRGs were also reviewed. Hospitalizations due to cardiac arrhythmias were approximately 26.000 per year and close to 1.6% for mortality. In 2010 there were 26.421 hospitalizations with an estimated cost of 65 million Euros. Frequent comorbidities were recorded, such as hypertension (43%), heart failure (12%) or diabetes mellitus (20%). A total of 43% were admitted to cardiology and 36% to internal medicine. During the period 1997-2010, there was a significant annual number of hospitalizations for cardiac arrhythmias (mainly atrial fibrillation), with measurable costs, in Spain. More than one third were attended by internists. Copyright © 2012 Elsevier España, S.L. All rights reserved.

  4. Case Report: Supraventricular Arrhythmia after Exposure to Concentrated Ambient Air Pollution Particles

    Science.gov (United States)

    Bassett, Maryann; Montilla, Tracey; Chung, Eugene H.; Smith, Candice B.; Cascio, Wayne E.; Carraway, Martha Sue

    2011-01-01

    Context: Exposure to air pollution can result in the onset of arrhythmias. Case presentation: We present a case of a 58-year-old woman who volunteered to participate in a controlled exposure to concentrated ambient particles. Twenty minutes into the exposure, telemetry revealed new onset of atrial fibrillation. The exposure was discontinued, and she reverted to normal sinus rhythm approximately 2 hr later. No abnormality was evident on the volunteer’s laboratory examination or echocardiography that could explain an increased risk for supraventricular arrhythmia. Discussion: Epidemiologic evidence strongly supports a relationship between exposure to air pollutants and cardiovascular disease, but population-level data are not directly relevant to the clinical presentation of individual cases. To our knowledge, this is the only case report of an individual suffering an episode of atrial fibrillation after exposure to an air pollutant. The resolution of the arrhythmia with termination of the particle exposure further supports a causal relationship between the two. Relevance to clinical practice: Exposure to air pollution, including particulate matter, may cause supraventricular arrhythmias. PMID:21896397

  5. Hypertension and cardiac arrhythmias : A consensus document fromthe European Heart RhythmAssociation (EHRA) and ESC Council on Hypertension, endorsed by the Heart RhythmSociety (HRS), Asia-Pacific Heart RhythmSociety (APHRS) and Sociedad Latinoamericana de Estimulacion Cardiaca y Electrofisiologia (SOLEACE)

    NARCIS (Netherlands)

    Lip, Gregory Y. H.; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S.; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S.; Steffel, Jan; Marin, Francisco; de Oliveira Figueiredo, Marcio Jansen; de Simone, Giovanni; Tzou, Wendy S.; Chiang, Chern-En; Williams, Bryan; Dan, Gheorghe-Andrei; Gorenek, Bulent; Fauchier, Laurent; Savelieva, Irina; Hatala, Robert; van Gelder, Isabelle; Brguljan-Hitij, Jana; Erdine, Serap; Lovic, Dragan; Kim, Young-Hoon; Salinas-Arce, Jorge; Field, Michael

    2017-01-01

    Hypertension is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease, stroke, peripheral artery disease and chronic renal insufficiency. Hypertensive heart disease can manifest as many cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both

  6. Atypical cardioversion in unstable arrhythmia caused by clavicle surgery

    Directory of Open Access Journals (Sweden)

    Stefan Bushuven

    2017-12-01

    Full Text Available We report on a 54-year old male with traumatic brain injury, flail chest and floating shoulder undergoing intramedullary stabilization of a midshaft clavicle fracture in beach chair position. Intraoperatively the patient developed instable atrial fibrillation triggered by implantation of intramedullary nail. Secondary this case shows feasibility of cardioversion in latero-lateral electrode-position due to inaccessible standard positions and patient fixation between the operation table and the X-ray apparatus.

  7. Managing atrial fibrillation in the elderly: critical appraisal of dronedarone

    Directory of Open Access Journals (Sweden)

    Trigo P

    2011-12-01

    Full Text Available Paula Trigo, Gregory W FischerDepartment of Anesthesiology, Mount Sinai School of Medicine, New York, NY, USAAbstract: Atrial fibrillation is the most commonly seen arrhythmia in the geriatric population and is associated with increased cardiovascular morbidity and mortality. Treatment of the elderly with atrial fibrillation remains challenging for physicians, because this unique subpopulation is characterized by multiple comorbidities requiring chronic use of numerous medications, which can potentially lead to severe drug interactions. Furthermore, age-related changes in the cardiovascular system as well as other physiological changes result in altered drug pharmacokinetics. Dronedarone is a new drug recently approved for the treatment of arrhythmias, such as atrial fibrillation and/or atrial flutter. Dronedarone is a benzofuran amiodarone analog which lacks the iodine moiety and contains a methane sulfonyl group that decreases its lipophilicity. These differences in chemical structure are responsible for making dronedarone less toxic than amiodarone which, in turn, results in fewer side effects. Adverse events for dronedarone include gastrointestinal side effects and rash. No dosage adjustments are required for patients with renal impairment. However, the use of dronedarone is contraindicated in the presence of severe hepatic dysfunction.Keywords: atrial fibrillation, elderly, antiarrhythmic agents, amiodarone, dronedarone

  8. Electrocardiographic artefacts mimicking atrial tachycardia resulted in unnecessary diagnostic and therapeutic measures

    OpenAIRE

    Y-Hassan, Shams; Sylv?n, Christer

    2013-01-01

    Electrocardiographic (ECG) artefacts may closely simulate both supraventricular and ventricular tachycardias. We describe a case initially diagnosed as rapid atrial fibrillation, based on 12-lead surface ECG (especially the limb leads) and monitor tracing. The arrhythmia was resistant to beta blockers. Because of the at times apparently regular rhythm, an esophageal ECG recording was performed, and adenosine was administered. When the presumed atrial fibrillation terminated after sodium pento...

  9. Prevention and Treatment of Arrhythmia

    Science.gov (United States)

    ... State SELECT YOUR LANGUAGE Español (Spanish) 简体中文 (Traditional Chinese) 繁体中文 (Simplified Chinese) Tiếng Việt (Vietnamese) Healthy Living for Heart.org ... doctor will set a treatment plan. View an animation of arrhythmia Treatment goals Especially for people with ...

  10. [Late potentials and ventricular arrhythmia].

    Science.gov (United States)

    Adamec, R; Zimmermann, M

    1986-04-01

    When electrodes are placed at the surface of the thorax, high-amplification electrocardiography (HA-ECG) combined with signal summation as a function of time provides a non-invasive method for detecting electric potentials occurring after the QRS complex of the clinical electrocardiogram. These potentials are called late, and can probably be likened to the "divided" or "fragmented" potentials recorded directly on the heart or in its ventricles near zones of ischemia, infarction or aneurysm. The prevalence of late potentials of ventricular activation (LPVA) and their association with the occurrence of ventricular arrhythmias seems well established, notably in the presence of ventricular aneurysm and anamnesis of severe ventricular arrhythmia. Some studies have shown that detection of LPVAs is of value in identifying heart patients at risk of ventricular arrhythmia or sudden death. Heart disease aside, the presence of LPVAs has been demonstrated in arrhythmogenic right ventricular dysplasia and reported in Fallot's tetralogy after complete correction. A standardization of recordings and a more precise definition of LPVAs are necessary before HA-ECG can become a routine clinical method. Further, the possibility of "beat by beat" recordings with "spatial" summation will allow detection of LPVAs which vary with time and in nature and hence provide a better understanding of the genesis of ventricular arrhythmias.

  11. Concomitant atrial fibrillation surgery: worth the effort?

    Science.gov (United States)

    Nashef, Samer A M; Abu-Omar, Yasir

    2017-12-08

    Concomitant surgery for atrial fibrillation is a conceptually and clinically difficult area of cardiac surgical decision making. This review introduces the pathophysiological background, provides insight and guidance for cardiac surgeons on some of the conflicting evidence and claims, and explores the fields in which further research may help elucidate a cardiac surgical clinical strategy for tackling this common and potentially lethal form of arrhythmia. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  12. Current approaches in atrial fibrillation treatment

    Directory of Open Access Journals (Sweden)

    Cenk Sarı

    2014-09-01

    Full Text Available Atrial fibrillation (AF is the most common sustained arrhythmia encountered in clinical practice. Its incidence increases with age. AF is classified into subtypes according to the duration and/or able to provide sinus rhytym. İnitially, patients should be evaluated for rhythm or rate control for appropriate treatment. Second stage of strategy aimed to investigate the feasibility of anticoagulation therapy. Recently, due to the progress made in treatment with rhythm control and anticoagulation therapy, either American or European guidelines have been renovated. These developments have taken place in the newly published guide. In this article, the current change in the management of AF is discussed.

  13. Rapidly detecting disorder in rhythmic biological signals: a spectral entropy measure to identify cardiac arrhythmias

    CERN Document Server

    Staniczenko, Phillip P A; Jones, Nick S

    2008-01-01

    We consider the use of a running measure of power spectrum disorder to distinguish between the normal sinus rhythm of the heart and two forms of cardiac arrhythmia: atrial fibrillation and atrial flutter. This is motivated by characteristic differences in the spectra of beats during the three rhythms. We plot patient data derived from 10-beat windows on a `disorder map' and identify rhythm-defining ranges in the level and variance of spectral entropy values. Employing the spectral entropy within an automatic arrhythmia detection algorithm enables the classification of periods of atrial fibrillation from the time series of patients' beats. When the algorithm is set to identify abnormal rhythms within 6s it agrees with 85.7% of the annotations of professional rhythm assessors; for a response time of 30s this becomes 89.5%, and with 60s it is 90.3%. The algorithm provides a rapid way to detect atrial fibrillation, demonstrating usable response times as low as six seconds. Measures of disorder in the frequency do...

  14. Stroke as the First Manifestation of Atrial Fibrillation.

    Science.gov (United States)

    Jaakkola, Jussi; Mustonen, Pirjo; Kiviniemi, Tuomas; Hartikainen, Juha E K; Palomäki, Antti; Hartikainen, Päivi; Nuotio, Ilpo; Ylitalo, Antti; Airaksinen, K E Juhani

    2016-01-01

    Atrial fibrillation may remain undiagnosed until an ischemic stroke occurs. In this retrospective cohort study we assessed the prevalence of ischemic stroke or transient ischemic attack as the first manifestation of atrial fibrillation in 3,623 patients treated for their first ever stroke or transient ischemic attack during 2003-2012. Two groups were formed: patients with a history of atrial fibrillation and patients with new atrial fibrillation diagnosed during hospitalization for stroke or transient ischemic attack. A control group of 781 patients with intracranial hemorrhage was compiled similarly to explore causality between new atrial fibrillation and stroke. The median age of the patients was 78.3 [13.0] years and 2,009 (55.5%) were women. New atrial fibrillation was diagnosed in 753 (20.8%) patients with stroke or transient ischemic attack, compared to 15 (1.9%) with intracranial hemorrhage. Younger age and no history of coronary artery disease or other vascular diseases, heart failure, or hypertension were the independent predictors of new atrial fibrillation detected concomitantly with an ischemic event. Thus, ischemic stroke was the first clinical manifestation of atrial fibrillation in 37% of younger (<75 years) patients with no history of cardiovascular diseases. In conclusion, atrial fibrillation is too often diagnosed only after an ischemic stroke has occurred, especially in middle-aged healthy individuals. New atrial fibrillation seems to be predominantly the cause of the ischemic stroke and not triggered by the acute cerebrovascular event.

  15. Atrial-selective K+ channel blockers: potential antiarrhythmic drugs in atrial fibrillation?

    Science.gov (United States)

    Ravens, Ursula

    2017-11-01

    In the wake of demographic change in Western countries, atrial fibrillation has reached an epidemiological scale, yet current strategies for drug treatment of the arrhythmia lack sufficient efficacy and safety. In search of novel medications, atrial-selective drugs that specifically target atrial over other cardiac functions have been developed. Here, I will address drugs acting on potassium (K+) channels that are either predominantly expressed in atria or possess electrophysiological properties distinct in atria from ventricles. These channels include the ultra-rapidly activating, delayed outward-rectifying Kv1.5 channel conducting IKur, the acetylcholine-activated inward-rectifying Kir3.1/Kir3.4 channel conducting IK,ACh, the Ca2+-activated K+ channels of small conductance (SK) conducting ISK, and the two-pore domain K+ (K2P) channels (tandem of P domains, weak inward-rectifying K+ channels (TWIK-1), TWIK-related acid-sensitive K+ channels (TASK-1 and TASK-3)) that are responsible for voltage-independent background currents ITWIK-1, ITASK-1, and ITASK-3. Direct drug effects on these channels are described and their putative value in treatment of atrial fibrillation is discussed. Although many potential drug targets have emerged in the process of unravelling details of the pathophysiological mechanisms responsible for atrial fibrillation, we do not know whether novel antiarrhythmic drugs will be more successful when modulating many targets or a single specific one. The answer to this riddle can only be solved in a clinical context.

  16. A Novel Nonsense Variant in Nav1.5 Cofactor MOG1 Eliminates Its Sodium Current Increasing Effect and May Increase the Risk of Arrhythmias

    DEFF Research Database (Denmark)

    Olesen, Morten S; Jensen, Niels F; Holst, Anders G

    2011-01-01

    BACKGROUND: The protein MOG1 is a cofactor of the cardiac sodium channel, Nav1.5. Overexpression of MOG1 in Nav1.5-expressing cells increases sodium current markedly. Mutations in the genes encoding Nav1.5 and its accessory proteins have been associated with cardiac arrhythmias of significant...... clinical impact. We sought to investigate whether MOG1 is implicated in cardiac arrhythmias. METHODS: We performed a genetic screening of the MOG1-encoding gene (gene symbol RANGRF, alias MOG1) in 220 Danish patients with cardiac arrhythmia. Of the 220, 197 were young patients with lone atrial fibrillation...

  17. Computer-assisted instruction of arrhythmia for MS-windows.

    Science.gov (United States)

    Takeuchi, A; Nara, Y; Ikeda, N; Miyahara, H; Mitobe, H

    1995-01-01

    1. INTRODUCTION. Training in the diagnosis of arrhythmias is an important part of the curriculum for medical students, postgraduates, and paramedical staff. Although several CAI for arrhythmia have been developed [1-3], we could not get CAI software for arrhythmia for the MS-Windows environment. In this report, we present a newly-developed computer-assisted reference system for arrhythmia that functions in the Windows environment. 2. DESCRIPTION OF THE SYSTEM. The system consists of a program and two data files. An MS-Windows program (ECG9405.EXE, 180kB) was compiled using Borland's C++ v.3.1. A binary file (ECPAT.BAS 33kB) includes data of normal and abnormal wave segments of ECG: P wave, PQ interval segment, and QRs complex with/without T wave. A mother file (ECG9405.sys, 57kB) includes 85 data sets to generate ECG waveforms of arrhythmia. Each data set contains a sequence of wave form numbers, the text for questions and answers, and the commands strings. There are five major commands: 1) to create a new window as "wave window"; 2) to make electrocardiogram data; 3) to plot the data on the window; 4) to create a "dialog box" for questions and explanations; and 5) to check the answers. he program gets a data set from the data according to the user's choice. The program then interprets the data set and executes the commands. The wave segment data are plotted in a "wave window" at every 10 milliseconds; this is controlled by the MS-Windows' timer. The timer interval can be changed by selecting the speed button. The ECG waveforms are displayed on a window just like an ordinary ECG monitor with beat sound. Many windows can be created by the user and many ECG waves simultaneously plotted on CRT. 3. USAGE OF THE SYSTEM. The "main window" has a menu that has three items corresponding to the training course: BASIC, TRY, and TEST. Thirty-five types of arrythmias are listed in the "list box" of the windows in BASIC course e.g., sinus arrhythmia, atrial flutter, atrial

  18. [Current classification of anti-arrhythmia agents].

    Science.gov (United States)

    Weirich, J; Wenzel, W

    2000-01-01

    Antiarrhythmic drugs can be divided into four Vaughan Williams classes (I-IV) according to defined electrophysiological effects on the myocardium. Thus, the Vaughan Williams classification also coincides with the main myocardial targets of the antiarrhythmics, i.e., myocardial sodium-, potassium-, and calcium-channels or beta-adrenergic receptors. A more detailed characterization which is also based on the myocardial targets of a drug is given by the "Sicilian Gambit" approach of classification. Nevertheless, the appropriate drug for the management of a given clinical arrhythmia has to be chosen according to the electrophysiological effects of the respective drug. A main determinant of the antiarrhythmic or proarrhythmic properties of a drug is the frequency dependence of its electrophysiological effects. The sodium-channel blockade induced by class-I substances is enhanced with increasing heart rates. Thus, class-I antiarrhythmics can be subclassified as substances showing a more exponential, an approximately linear, or rather saturated block-frequency relation. Class-III antiarrhythmics (potassium-channel blockade) can be further differentiated according to the component of the delayed rectifier potassium current (IK) which is inhibited by a drug. Class-III drugs inhibiting selectively the rapidly activating and deactivating IKr component exhibit a marked reverse rate dependence, i.e., the drug induced prolongation of the cardiac action potential is minimized at high rates. On the other hand, during bradycardia the pronounced action potential prolongation may cause early afterdepolarizations and triggered activity leading to torsades de pointes arrhythmias (acquired QT syndrome). Class-III substances inhibiting the slowly activating IKs component are currently under investigation and are expected to show a direct rate dependence. Experimental data available so far point to an action potential prolonging effect at least independent of rate. However, it is

  19. Unexpected guest: Atrial fibrillation due to electrical shock

    Directory of Open Access Journals (Sweden)

    Mehmet Zihni Bilik

    2016-03-01

    Full Text Available Cardiac arrhythmias due to electrical injuries are rare among emergency service admittances. A 35 year-old female patient was admitted to emergency service with palpitation after electrical injury as a result of contact with a domestic low-voltage source. Electrocardiography (ECG showed atrial fibrillation with rapid ventricular response. Transthoracic echocardiography findings were normal. Atrial fibrillation spontaneously converted to normal sinus rhythm after rate limiting treatment with beta-blocker. The patient was discharged without any complication on the third day of hospitalization. Although cardiac arrhythmias rarely occur after electrical injury, cardiac monitoring is recommended for all patients with documented rhythm disorder, loss of consciousness, or abnormal ECG at admission.

  20. New theory of arrhythmia. Conceptual substantiation of arrhythmia mechanisms

    Directory of Open Access Journals (Sweden)

    Vladimir I. Ermoshkin

    2015-11-01

    Full Text Available Aims A new attempt is made to substantiate the concept of the mechanism of arrhythmia and sudden cardiac death. Methods The paper is based on a theoretical analysis of special literature, personal experience of participation in conferences and discussions with leading Russian cardiologists. Results We have succeeded in demonstrating the fact that researchers ignore the fact that cardiomyocytes can be excited by mechanical pulses, when considering the arrhythmia mechanisms. We have conducted trials using the Cardiocode device. Under stress in a human, opened may be large and small arteriovenous anastomoses, via which blood under high pressure is ejected into veins. It leads to pressure surges in arteries and veins. The vena cava dilates, its tonus increases. In some cases, the pulse waves travel via anastomoses along the vena cava walls to the atria and the ventricles. An above-threshold concentration of tensions from mechanical pulses may excite cardiomyocytes from different points of the myocardium, disturbing the sinus rhythm. As a result, extrasystoles, tachycardia attacks, blocking of blood circulation in the peripheral segments of the venous arterial networks, edemata, thrombosis and metabolism disorders appear. Arrhythmia, tachycardia attacks and concomitant myocardial ischemia lead to progression of heart fibrosis. Such changes increase the probability of fibrillations and sudden cardiac death. Conclusion Unhealthy lifestyle, the presence of opening and not properly closing anastomoses may provoke a number of diseases. To avoid the cardiac arrhythmia attacks and prevent SCD, it is necessary to suppress travel of the mechanical waves within the following circuitry: aorta – artery – anastomosis – vein – vena cava – atria – ventricles. The travel of the mechanical waves within the same vessel circuitry explains the fact that the fixed couplings under extrasystoles are observed, and the beat-to-beat RR intervals under tachycardia

  1. Could successful cryoballoon ablation of paroxysmal atrial fibrillation prevent progressive left atrial remodeling?

    Science.gov (United States)

    Erdei, Tamás; Dénes, Mónika; Kardos, Attila; Mihálcz, Attila; Földesi, Csaba; Temesvári, András; Lengyel, Mária

    2012-03-19

    Radiofrequency catheter ablation of atrial fibrillation (AF) has been proved to be effective and to prevent progressive left atrial (LA) remodeling. Cryoballoon catheter ablation (CCA), using a different energy source, was developed to simplify the ablation procedure. Our hypothesis was that successful CCA can also prevent progressive LA remodeling. 36 patients selected for their first CCA because of nonvalvular paroxysmal AF had echocardiography before and 3, 6 and 12 months after CCA. LA diameters, volumes (LAV) and LA volume index (LAVI) were evaluated. LA function was assessed by: early diastolic velocities of the mitral annulus (Aa(sept), Aa(lat)), LA filling fraction (LAFF), LA emptying fraction (LAEF) and the systolic fraction of pulmonary venous flow (PVSF). Detailed left ventricular diastolic function assessment was also performed. Excluding recurrences in the first 3-month blanking period, the clinical success rate was 64%. During one-year of follow-up, recurrent atrial arrhythmia was found in 21 patients (58%). In the recurrent group at 12 months after ablation, minimal LAV (38 ± 19 to 44 ± 20 ml; p < 0.05), maximal LAV (73 ± 23 to 81 ± 24 ml; p < 0.05), LAVI (35 ± 10 to 39 ± 11 ml/m2; p = 0.01) and the maximal LA longitudinal diameter (55 ± 5 to 59 ± 6 mm; p < 0.01) had all increased. PVSF (58 ± 9 to 50 ± 10%; p = 0.01) and LAFF (36 ± 7 to 33 ± 8%; p = 0.03) had decreased. In contrast, after successful cryoballoon ablation LA size had not increased and LA function had not declined. In the recurrent group LAEF was significantly lower at baseline and at follow-up visits. In patients whose paroxysmal atrial fibrillation recurred within one year after cryoballoon catheter ablation left atrial size had increased and left atrial function had declined. In contrast, successful cryoballoon catheter ablation prevented progressive left atrial remodeling.

  2. Could successful cryoballoon ablation of paroxysmal atrial fibrillation prevent progressive left atrial remodeling?

    Directory of Open Access Journals (Sweden)

    Erdei Tamás

    2012-03-01

    Full Text Available Abstract Background Radiofrequency catheter ablation of atrial fibrillation (AF has been proved to be effective and to prevent progressive left atrial (LA remodeling. Cryoballoon catheter ablation (CCA, using a different energy source, was developed to simplify the ablation procedure. Our hypothesis was that successful CCA can also prevent progressive LA remodeling. Methods 36 patients selected for their first CCA because of nonvalvular paroxysmal AF had echocardiography before and 3, 6 and 12 months after CCA. LA diameters, volumes (LAV and LA volume index (LAVI were evaluated. LA function was assessed by: early diastolic velocities of the mitral annulus (Aasept, Aalat, LA filling fraction (LAFF, LA emptying fraction (LAEF and the systolic fraction of pulmonary venous flow (PVSF. Detailed left ventricular diastolic function assessment was also performed. Results Excluding recurrences in the first 3-month blanking period, the clinical success rate was 64%. During one-year of follow-up, recurrent atrial arrhythmia was found in 21 patients (58%. In the recurrent group at 12 months after ablation, minimal LAV (38 ± 19 to 44 ± 20 ml; p p 2; p = 0.01 and the maximal LA longitudinal diameter (55 ± 5 to 59 ± 6 mm; p p = 0.01 and LAFF (36 ± 7 to 33 ± 8%; p = 0.03 had decreased. In contrast, after successful cryoballoon ablation LA size had not increased and LA function had not declined. In the recurrent group LAEF was significantly lower at baseline and at follow-up visits. Conclusions In patients whose paroxysmal atrial fibrillation recurred within one year after cryoballoon catheter ablation left atrial size had increased and left atrial function had declined. In contrast, successful cryoballoon catheter ablation prevented progressive left atrial remodeling.

  3. Cardiac Arrhythmias: Diagnosis, Symptoms, and Treatments.

    Science.gov (United States)

    Fu, Du-Guan

    2015-11-01

    The cardiac arrhythmia is characterized by irregular rhythm of heartbeat which could be either too slow (100 beats/min) and can happen at any age. The use of pacemaker and defibrillators devices has been suggested for heart arrhythmias patients. The antiarrhythmic medications have been reported for the treatment of cardiac arrhythmias or irregular heartbeats. The diagnosis, symptoms, and treatments of cardiac arrhythmias as well as the radiofrequency ablation, tachycardia, Brugada syndrome, arterial fibrillation, and recent research on the genetics of cardiac arrhythmias have been described here.

  4. Risk of atrial fibrillation with high-dose corticosteroids.

    Science.gov (United States)

    Chiappini, Bruno; El Khoury, Gebrine

    2006-11-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia observed in clinical practice. Some drugs have been associated with the onset of AF, but knowledge about the role of drugs in the development of AF is scarce. High-dose corticosteroid therapy has been associated with the development of AF, but this is mainly based on case reports. Therefore, the authors review the available data in the international literature about the cause-effect relationship between corticosteroid therapy and the onset of AF.

  5. Cardiac Arrhythmias in Patients with Chronic Kidney Disease: Implications of Renal Failure for Antiarrhythmic Drug Therapy.

    Science.gov (United States)

    Potpara, Tatjana S; Jokic, Vera; Dagres, Nikolaos; Marin, Francisco; Prostran, Milica S; Blomstrom-Lundqvist, Carina; Lip, Gregory Y H

    2016-01-01

    The kidney has numerous complex interactions with the heart, including shared risk factors (e.g., hypertension, dyslipidemia, etc.) and mutual amplification of morbidity and mortality. Both cardiovascular diseases and chronic kidney disease (CKD) may cause various alterations in cardiovascular system, metabolic homeostasis and autonomic nervous system that may facilitate the occurrence of cardiac arrhythmias. Also, pre-existent or incident cardiac arrhythmias such as atrial fibrillation (AF) may accelerate the progression of CKD. Patients with CKD may experience various cardiac rhythm disturbances including sudden cardiac death. Contemporary management of cardiac arrhythmias includes the use of antiarrhythmic drugs (AADs), catheter ablation and cardiac implantable electronic devices (CIEDs). Importantly, AADs are not used only as the principal treatment strategy, but also as an adjunct therapy in combination with CIEDs, to facilitate their effects or to minimize inappropriate device activation in selected patients. Along with their principal antiarrhythmic effect, AADs may also induce cardiac arrhythmias and the risk for such proarrhythmic effect(s) is particularly increased in patients with reduced left ventricular systolic function or in the setting of electrolyte imbalance. Moreover, CKD itself can induce profound alterations in the pharmacokinetics and pharmacodynamics of many drugs including AADs, thus facilitating the drug accumulation and increased exposure. Hence, the use of AADs in patients with CKD may be challenging. In this review article, we provide an overview of the characteristics of arrhythmogenesis in patients with CKD with special emphasis on the complexity of pharmacokinetics and risk for proarrhythmias when using AADs in patients with cardiac arrhythmias and CKD.

  6. T wave alternans for ventricular arrhythmia risk stratification.

    Science.gov (United States)

    Gold, Michael R; Spencer, William

    2003-01-01

    Sudden cardiac death remains one of the leading causes of death in western societies. Accordingly, the ability to identify patients at high risk of sudden cardiac death is important so that appropriate treatments can be used efficiently. Recently, T wave alternans (TWA) has emerged as a promising new test for such risk stratification. TWA is a heart rate-dependent measure of arrhythmia vulnerability, with maximal predictive accuracy at sustained, regular heart rates of 100 to 120 bpm. In the clinical setting, these conditions may be achieved by either exercise or atrial pacing. TWA has been shown to predict inducibility of ventricular tachycardia with programmed stimulation and also spontaneous arrhythmic events. TWA has been successfully applied to diverse populations, including patients with coronary artery disease, nonischemic cardiomyopathy, congestive heart failure, and implantable defibrillators. Despite these encouraging results, the role of TWA to guide clinical therapy still needs to be elucidated better.

  7. Serious arrhythmias in patients with apical hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Okishige, Kaoru; Sasano, Tetsuo; Yano, Kei; Azegami, Kouji; Suzuki, Kou; Itoh, Kuniyasu [Yokohama Red Cross Hospital (Japan)

    2001-05-01

    We report cases of serious arrhythmias associated with apical hypertrophic cardiomyopathy (AHCM). Thirty-one patients were referred to our institute to undergo further assessment of their AHCM from 1988 to 1999. Three patients with nonsustained ventricular tachycardia demonstrated an {sup 123}I-MIBG regional reduction in the tracer uptake. In two patients with ventricular fibrillation (VF), the findings from {sup 123}I-MIBG imaging revealed regional sympathetic denervation in the inferior and lateral regions. Electrophysiologic study demonstrated reproducible induction of VF in aborted sudden death and presyncopal patients, resulting in the need for an implantable defibrillator device and amiodarone in each patient. Patients with refractory atrial fibrillation with a rapid ventricular response suffered from serious congestive heart failure. A prudent assessment and strategy in patients with this disease would be indispensable in avoiding a disastrous outcome. (author)

  8. Heart transplantation mysteriously eliminates arrhythmia

    Directory of Open Access Journals (Sweden)

    Vladimir I. Ermoshkin

    2016-05-01

    Full Text Available For a long time cardiologists have not been able to explain why the problem of cardiac arrhythmia in a heart transplant recipient practically disappears. In fact, this issue has never been raised for discussion. At the same time, my new theory of arrhythmias (NTA has been discussed at conferences and in mass media for the last 4 years. The core proposition of NTA is as follows: the generation of extrasystoles and tachycardia in most cases occurs not due to bioelectric reentry, but owing to the action of mechanical pulse waves. A pathological pulse wave can travel to large veins along the walls of the arteriovenous anastomoses (AVA and excite cardiomyocytes. The developer of NTA has studied some peculiarities of the cardiac rhythm patterns which occur after heart transplantation and presents herein convincing evidence in favor of his new theory.

  9. The hypothesis of cardiac arrhythmias

    OpenAIRE

    Ermoshkin, Vladimir

    2013-01-01

    Background. Cardiovascular diseases(CVDs) are the main causes of death in all countries. Majority of these deaths occur due to arrhythmias. The aim of this review to attempt to propose new hypothesis regarding the pathogenesis of extrasystoles and pathological tachycardia. Methods. Internet search and discussion with experts: Frolov V.M., Shirokov E.A., Singh R.B. et al. Results. The extrasystoles and tachycardia occur in some people due to the pulse propagation through abnormal contour of ve...

  10. Usefulness of vernakalant hydrochloride injection for rapid conversion of atrial fibrillation

    DEFF Research Database (Denmark)

    Pratt, Craig M.; Roy, Dennis; Torp-Pedersen, Christian

    2010-01-01

    The objective of the present study was to assess the safety and effectiveness of vernakalant hydrochloride injection (RSD1235), a novel antiarrhythmic drug, for the conversion of atrial fibrillation (AF) or atrial flutter to sinus rhythm (SR). Patients with either AF or atrial flutter were...... infusion of placebo or vernakalant (2 mg/kg) 15 minutes later if the arrhythmia had not terminated. A total of 265 patients were randomized and received treatment. The primary end point was conversion of AF to SR for ≥1 minute within 90 minutes of the start of the drug infusion in the short-duration AF...

  11. Catheter ablation of cardiac arrhythmias in pregnancy without fluoroscopy: A case control retrospective study.

    Science.gov (United States)

    Koźluk, Edward; Piątkowska, Agnieszka; Kiliszek, Marek; Lodziński, Piotr; Małkowska, Sylwia; Balsam, Paweł; Rodkiewicz, Dariusz; Piątkowski, Radosław; Zyśko, Dorota; Opolski, Grzegorz

    2017-01-01

    Cardiac arrhythmias are common in pregnant women. In most cases, they do not require treatment other than rest, electrolyte supplementation and avoidance of strong coffee and tea. Persistent arrhythmia or the ventricular rate running at a high frequency may cause hemodynamic deterioration in the fetus or in both the fetus and the mother. The aim of this study was to assess the prevalence and characteristics of arrhythmias in pregnant women who qualified for ablation as well as the feasibility and specific features of these interventions. The study group consisted of 11 pregnant women (16-32 Hbd) aged 31 + 6. The control group consisted of 111 women aged 15-50 years (34 + 10), scheduled for ablation in 2012. The medical records of the selected study and control groups were analyzed and the following data was retrieved: age, the reason the ablation procedure was performed, the ablation duration, the number of radiofrequency applications, the total duration of radiofrequency applications, gravity, and comorbidities. In the study group, accessory pathway related arrhythmias or atrial tachycardia (AT) accounted for 62% of cases, whereas in the control group for 32% (p = 0.042). All the procedures in the study group were performed with an electroanatomical system without fluoroscopy. All of the patients, but one, had no recurrence of arrhythmia. There were no complications and no overt effects were noted in the fetus. Ablation of arrhythmias during pregnancy is rare. An experienced surgeon using electroanatomical system is usually able to ablate arrhythmic substrate without the use of X-ray fluoroscopy. The most prevalent causes of arrhythmias in pregnant women requiring ablation are accessory pathway and AT focus.

  12. Magnesium sulphate and amiodarone prophylaxis for prevention of postoperative arrhythmia in coronary by-pass operations

    Directory of Open Access Journals (Sweden)

    Huysal Kagan

    2009-02-01

    Full Text Available Abstract Background The aim of this study was to investigate the use of prophylactic magnesium sulphate and amiodarone in treating arrhythmias that may occur following coronary bypass grafting operations. Methods The study population consisted of 192 consecutive patients who were undergoing coronary artery bypass grafting (CABG. Sixty-four patients were given 3 g of magnesium sulphate (MgSO4 [20 ml = 24.32 mEq/L Mg+2] in 100 cc of isotonic 0.9% solution over 2 hours intravenously at the following times: 12 hours prior to the operation, immediately following the operation, and on postoperative days 1, 2, and 3 (Group 1. Another group of 64 patients was given a preoperative infusion of amiodarone (1200 mg on first post-operative day (Group 2. After the operation amiodarone was administered orally at a dose of 600 mg/day. Sixty-four patients in group 3 (control group had 100 cc. isotonic 0.9% as placebo, during the same time periods. Results In the postoperative period, the magnesium values were significantly higher in Group 1 than in Group 2 for all measurements. The use of amiodarone for total arrhythmia was significantly more effective than prophylactic treatment with magnesium sulphate (p = 0.015. There was no difference between the two drugs in preventing supraventricular arrhythmia, although amiodarone significantly delayed the revealing time of atrial fibrillation (p = 0.026. Ventricular arrhythmia, in the form of ventricular extra systole, was more common in the magnesium prophylaxis group. The two groups showed no significant differences in other operative or postoperative measurements. No side effects of the drugs were observed. Conclusion Prophylactic use of magnesium sulphate and amiodarone are both effective at preventing arrhythmia that may occur following coronary by-pass operations. Magnesium sulphate should be used in prophylactic treatment since it may decrease arrhythmia at low doses. If arrhythmia should occur despite this

  13. The predictive value of CHADS₂ risk score in post myocardial infarction arrhythmias - a Cardiac Arrhythmias and RIsk Stratification after Myocardial infArction (CARISMA) substudy.

    Science.gov (United States)

    Ruwald, Anne Christine; Gang, Uffe; Thomsen, Poul Erik Bloch; Jørgensen, Rikke Mørch; Ruwald, Martin H; Huikuri, Heikki V; Jons, Christian

    2014-05-15

    Previous studies have shown substantially increased risk of cardiac arrhythmias and sudden cardiac death in post-myocardial infarction (MI) patients. However it remains difficult to identify the patients who are at highest risk of arrhythmias in the post-MI setting. The purpose of this study was to investigate if CHADS₂ score (congestive heart failure, hypertension, age ≥75 years, diabetes and previous stroke/TCI [doubled]) can be used as a risk tool for predicting cardiac arrhythmias after MI. The study included 297 post-MI patients from the CARISMA study with left ventricular ejection fraction (LVEF) ≤40%. All patients were implanted with an implantable cardiac monitor (ICM) within 5 to 21 days post-MI and followed every three months for two years. Atrial fibrillation, bradyarrhythmias and ventricular tachycardias were diagnosed using the ICM, pacemaker or ICD. Patients were stratified according to CHADS₂ score at enrollment. Congestive heart failure was defined as LVEF ≤40% and NYHA class II, III or IV. We found significantly increased risk of an arrhythmic event with increasing CHADS₂ score (CHADS₂ score=1-2: HR=2.1 [1.1-3.9], p=0.021, CHADS₂ score ≥ 3: HR=3.7 [1.9-7.1], pcardiac arrhythmias. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Atrial Cardiomyopathy: A Useful Notion in Cardiac Disease Management or a Passing Fad?

    Science.gov (United States)

    Guichard, Jean-Baptiste; Nattel, Stanley

    2017-08-08

    The term atrial cardiomyopathy, which has been used sporadically in the medical literature, was recently the subject of a detailed Consensus Document prepared by representatives of the European Heart Rhythm Association, Heart Rhythm Society, Asia-Pacific Heart Rhythm Society, and Sociedad Latinoamericana de Estimulación Cardiaca y Electrofisiología. They discussed aspects of the definition, histopathology, atrial-specific physiology, atrial pathology, impact on arrhythmia occurrence, imaging, mapping, and ablation. Here, the authors consider critically the added clinical value of this concept and its meaningfulness. They review evidence implicating atrial cardiomyopathy as an independent contributor to the risk of stroke associated with atrial fibrillation and as a determinant of arrhythmia progression. The issue of classification is considered and the authors discuss how atrial cardiomyopathic properties might guide stroke prevention, rhythm maintenance, and rate control in atrial fibrillation. Carefully designed clinical trials are needed to evaluate these potential applications, and will ultimately define the value of this terminology. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  15. Cardiac arrhythmias during fiberoptic bronchoscopy and relation with oxygen saturation

    Directory of Open Access Journals (Sweden)

    Hassan G

    2005-01-01

    Full Text Available To evaluate the occurrence of electrocardiographic abnormalities during fiberoptic bronchoscopy, in relation to specific stages of the procedures, patients′ age, sex, smoking, pre-existing lung disease, premedication and oxygen saturation, a prospective study was conducted on 56 patients aged 35 to 75 (mean 62 years without pre-existing cardiovascular disease. Patients were connected to a 12-lead computerized electrocardiographic recorder and pulse oximeter. Fall of oxygen saturation from mean of 95.12% before the procedure to below 80% was observed in 12 (21.4% patients and below 75% in 5 (8.9% patients, at various stages. Statistically highly significant (p < 0.001 fall of oxygen saturation was observed during the procedures while bronchoscope was introduced into the airways and tracheobronchial tree examined. Major disturbances of cardiac rhythm (i.e. atrial, ventricular or both developed in 23 (41.07% patients. Out of these, sinus tachycardia was noted in 16 (69.5%, ventricular premature complexes in 5 (21.7% and paroxysmal supraventricular tachycardia in 2 (8.6% patients. Arrhythmias were most frequent in association with periods of maximum oxygen desaturation in 18 (78.2% of these 23 patients. Oxygen desaturation persisted for more than half an hour in 38 (67.8% of the 56 patients. However, no correlation was observed between the frequency of arrhythmias during bronchoscopy and patients′ age, sex pre-medication or pre-existing pulmonary disease.

  16. Sex-specific increase in the prevalence of atrial fibrillation (The Copenhagen City Heart Study)

    DEFF Research Database (Denmark)

    Friberg, Jens; Scharling, Henrik; Gadsbøll, Niels

    2003-01-01

    Atrial fibrillation (AF) is the most frequently encountered cardiac arrhythmia. It is a risk factor for stroke and premature death. We studied the temporal changes in the prevalence of AF from 1976 to 1994 in a random population aged 50 to 89 years. The prevalence of AF, diagnosed from...

  17. Role of PR-Interval In Predicting the Occurrence of Atrial Fibrillation

    DEFF Research Database (Denmark)

    Bidstrup, Signe Brøker; Salling Olesen, Morten; Hastrup Svendsen, Jesper

    2013-01-01

    The identification of individuals at high risk of developing atrial fibrillation (AF) is important to prevent potentially lethal and invalidating complications of this arrhythmia. Recently, several studies have investigated the association between PR-interval and the risk of AF and have tested th...

  18. Vitamin D deficiency is unrelated to type of atrial fibrillation and its complications

    DEFF Research Database (Denmark)

    Qayyum, Faiza; Landex, Nadia Lander; Agner, Bue Ross

    2012-01-01

    Vitamin D plays an important role in a broad range of organ functions, including the cardiovascular system. Only one study has tested the association between vitamin D deficiency and arrhythmia and it found no association. The aim of the present study was to evaluate the association between vitamin...... D deficiency and the type of atrial fibrillation (AF) and complications to AF....

  19. Integrating genetic, transcriptional, and functional analyses to identify 5 novel genes for atrial fibrillation

    DEFF Research Database (Denmark)

    Sinner, Moritz F; Tucker, Nathan R; Lunetta, Kathryn L

    2014-01-01

    BACKGROUND: Atrial fibrillation (AF) affects >30 million individuals worldwide and is associated with an increased risk of stroke, heart failure, and death. AF is highly heritable, yet the genetic basis for the arrhythmia remains incompletely understood. METHODS AND RESULTS: To identify new AF-re...

  20. Catheter ablation of atrial tachycardia after interatrial defect repair with patch apposition.

    Science.gov (United States)

    Nguyen, B L; Garante, C M; Tersigni, F; Sergiacomi, R; Petrassi, M; Di Matteo, A; Tufano, F; Alessandri, N

    2012-02-01

    A 54-year-old woman with history of septal atrial mixoma surgically treated and drug-refractory supraventricular tachyarrhythmia underwent catheter ablation of macro-reentry areas near the pericardial patch placed to repair an interatrial defect. The use of ablative therapy has been successful to cure this arrhythmia.

  1. Reduced lung function and risk of atrial fibrillation in the Copenhagen City Heart Study

    DEFF Research Database (Denmark)

    Buch, P; Friberg, J; Scharling, H

    2003-01-01

    Chronic obstructive pulmonary disease has been associated with a high frequency of arrhythmias. Few studies have analysed the role of reduced lung function in predicting atrial fibrillation (AF). The aim of the present study was to investigate the relationship between forced expiratory volume in ...

  2. Focal Left Atrial Tachycardia in a Patient with Left Ventricular Noncompaction

    Directory of Open Access Journals (Sweden)

    Shailendra Singh

    2013-01-01

    Full Text Available Left ventricular noncompaction (LVNC is a rare disease caused by intrauterine failure of the myocardium to compact. The major clinical manifestations of LVNC include heart failure, ventricular tachyarrhythmia, thromboembolic event, and sudden deaths. Atrial arrhythmia usually seen is atrial fibrillation. We report a rare case of focal left atrial tachycardia in an 18-year-old patient who presented for evaluation of persistent tachycardia. Transthoracic echocardiogram showed severe systolic dysfunction and evidence of noncompaction of the left ventricle. A detailed review of ECG revealed the possibility of ectopic atrial tachycardia, most likely originating from the left side. Electrophysiology study showed sustained atrial tachycardia originating on the ridge anterior to the left sided pulmonary veins. A successful radiofrequency catheter ablation was performed at this site without any complications.

  3. Intermittent changing axis deviation with intermittent left anterior hemiblock during atrial flutter with subclinical hyperthyroidism.

    Science.gov (United States)

    Patanè, Salvatore; Marte, Filippo

    2009-06-26

    Subclinical hyperthyroidism is an increasingly recognized entity that is defined as a normal serum free thyroxine and free triiodothyronine levels with a thyroid-stimulating hormone level suppressed below the normal range and usually undetectable. It has been reported that subclinical hyperthyroidism is not associated with CHD or mortality from cardiovascular causes but it is usually associated with a higher heart rate and a higher risk of supraventricular arrhythmias including atrial fibrillation and atrial flutter. Intermittent changing axis deviation during atrial fibrillation has also rarely been reported. We present a case of intermittent changing axis deviation with intermittent left anterior hemiblock in a 59-year-old Italian man with atrial flutter and subclinical hyperthyroidism. To our knowledge, this is the first report of intermittent changing axis deviation with intermittent left anterior hemiblock in a patient with atrial flutter.

  4. Hybrid therapy in the management of atrial fibrillation.

    Science.gov (United States)

    Starek, Zdenk; Lehar, Frantisek; Jez, Jiri; Wolf, Jiri; Novák, Miroslav

    2015-01-01

    Atrial fibrillation is the most common sustained arrhythmia. Because of the sub-optimal outcomes and associated risks of medical therapy as well as the recent advances in non-pharmacologic strategies, a multitude of combined (hybrid) algorithms have been introduced that improve efficacy of standalone therapies while maintaining a high safety profile. Antiarrhythmic administration enhances success rate of electrical cardioversion. Catheter ablation of antiarrhythmic drug-induced typical atrial flutter may prevent recurrent atrial fibrillation. Through simple ablation in the right atrium, suppression of atrial fibrillation may be achieved in patients with previously ineffective antiarrhythmic therapy. Efficacy of complex catheter ablation in the left atrium is improved with antiarrhythmic drugs. Catheter ablation followed by permanent pacemaker implantation is an effective and safe treatment option for selected patients. Additional strategies include pacing therapies such as atrial pacing with permanent pacemakers, preventive pacing algorithms, and/or implantable dual-chamber defibrillators are available. Modern hybrid strategies combining both epicardial and endocardial approaches in order to create a complex set of radiofrequency lesions in the left atrium have demonstrated a high rate of success and warrant further research. Hybrid therapy for atrial fibrillation reviews history of development of non-pharmacological treatment strategies and outlines avenues of ongoing research in this field.

  5. Inflammation and atrial remodeling after a mountain marathon.

    Science.gov (United States)

    Wilhelm, M; Zueger, T; De Marchi, S; Rimoldi, S F; Brugger, N; Steiner, R; Stettler, C; Nuoffer, J-M; Seiler, C; Ith, M

    2014-06-01

    Endurance athletes have an increased risk of atrial fibrillation. We performed a longitudinal study on elite runners of the 2010 Jungfrau Marathon, a Swiss mountain marathon, to determine acute effects of long-distance running on the atrial myocardium. Ten healthy male athletes were included and examined 9 to 1 week prior to the race, immediately after, and 1, 5, and 8 days after the race. Mean age was 34.9 ± 4.2 years, and maximum oxygen consumption was 66.8 ± 5.8 mL/kg*min. Mean race time was 243.9 ± 17.7 min. Electrocardiographic-determined signal-averaged P-wave duration (SAPWD) increased significantly after the race and returned to baseline levels during follow-up (128.7 ± 10.9 vs. 137.6 ± 9.8 vs. 131.5 ± 8.6 ms; P marathon running was associated with a transient conduction delay in the atria, acute inflammation and increased atrial wall tension. This may reflect exercise-induced atrial myocardial edema and may contribute to atrial remodeling over time, generating a substrate for atrial arrhythmias. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. [Study of depressiveness with Beck Depression Inventory in patients with cardiac arrhythmias].

    Science.gov (United States)

    Hajduk, Anna; Korzonek, Maria; Przybycień, Krzysztof; Ertmański, Sławomir; Stolarek, Jolanta

    2011-01-01

    Atrial fibrillation belongs to the group of supraventricular arrhythmias. The episode begins with anxiety about the loss of health or life. Anxiety is accompanied by depressive disorders. The aim of this work was to study the intensity of depression in patients with atrial fibrillation. We used Beck Depression Inventory in 52 patients with atrial fibrillation hospitalized at the Department of Internal Medicine of the Poviat Hospital in Białogard. Correlations between the intensity of depression and age, gender, and education level were determined. The intensity of depression depended on age, gender, and education level. Mild depression was more common in women, moderate in men, and was very severe in 2 women. Patients between the age of 61 and 80 years and with incomplete primary and vocational education presented with all forms of depression. The intensity of depression correlates with episodes of atrial fibrillation and depends on such factors as age, gender, and education level (p Effective therapy of atrial fibrillation may help reduce the intensity of depression.

  7. Fluoroless Catheter Ablation of Cardiac Arrhythmias: A 5-Year Experience.

    Science.gov (United States)

    Razminia, Mansour; Willoughby, Michael Cameron; Demo, Hany; Keshmiri, Hesam; Wang, Theodore; D'Silva, Oliver J; Zheutlin, Terry A; Jibawi, Hakeem; Okhumale, Paul; Kehoe, Richard F

    2017-04-01

    Catheter ablations have been traditionally performed with the use of fluoroscopic guidance, which exposes the patient and staff to the inherent risks of radiation. We have developed techniques to eliminate the use of fluoroscopy during cardiac ablations and have been performing completely fluoroless catheter ablations on our patients for over 5 years. We present a retrospective analysis of the safety, efficacy, and feasibility data from 500 consecutive patients who underwent nonfluoroscopic catheter ablation, targeting a total of 639 arrhythmias, including atrioventricular reciprocating tachycardia (AVRT), atrioventricular nodal reentrant tachycardia (AVNRT), atrial tachycardia (AT), atrial fibrillation (AF), premature ventricular contractions (PVCs), and ventricular tachycardia (VT). We perform fluoroless ablations using intracardiac electrograms, electroanatomic mapping, and for most cases intracardiac echocardiography. Our experience includes exclusively endocardial cardiac ablations. The mean follow-up was 20.5 months. Recurrence rate for AVRT was 6.5%, for AVNRT 2.5%, for macro-reentrant AT 6.4%, for focal AT 5.4%, for AF 22.6%, for PVC 6.7%, and for VT 21.4%. Major complications occurred in five patients (1.0%); minor complications occurred in three patients (0.6%). No deaths occurred. Fluoroscopy was used in one instance, for 0.3 minutes, to confirm venous access. Completely fluoroless catheter ablations may be routinely performed for all endocardial ablations without compromising safety, efficacy, or procedural duration. © 2017 The Authors. Pacing and Clinical Electrophysiology published by Wiley Periodicals, Inc.

  8. Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

    Science.gov (United States)

    Smorodinova, Natalia; Bláha, Martin; Melenovský, Vojtěch; Rozsívalová, Karolína; Přidal, Jaromír; Ďurišová, Mária; Pirk, Jan; Kautzner, Josef; Kučera, Tomáš

    2017-01-01

    Atrial fibrillation (AF) is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients. The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR). We examined 46 subjects (19 with AF, and 27 in SR) undergoing coronary bypass or valve surgery. Peroperative bioptic samples of the left and the right atrial tissue were examined using immunohistochemistry. The number of CD3+ T-lymphocytes and CD68-KP1+ cells were elevated in the left atrial myocardium of patients with AF compared to those in SR. Immune cell infiltration of LA was related to the rhythm, but not to age, body size, LA size, mitral regurgitation grade, type of surgery, systemic markers of inflammation or presence of diabetes or hypertension. Most of CD68-KP1+ cells corresponded to dendritic cell population based on their morphology and immunoreactivity for DC-SIGN. The numbers of mast cells and CD20+ B-lymphocytes did not differ between AF and SR patients. No foci of inflammation were detected in any sample. An immunohistochemical analysis of samples from patients undergoing open heart surgery showed moderate and site-specific increase of inflammatory cells in the atrial myocardium of patients with AF compared to those in SR, with prevailing population of monocyte-macrophage lineage. These cells and their cytokine products may play a role in atrial remodeling and AF persistence.

  9. Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

    Directory of Open Access Journals (Sweden)

    Natalia Smorodinova

    Full Text Available Atrial fibrillation (AF is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients.The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR.We examined 46 subjects (19 with AF, and 27 in SR undergoing coronary bypass or valve surgery. Peroperative bioptic samples of the left and the right atrial tissue were examined using immunohistochemistry.The number of CD3+ T-lymphocytes and CD68-KP1+ cells were elevated in the left atrial myocardium of patients with AF compared to those in SR. Immune cell infiltration of LA was related to the rhythm, but not to age, body size, LA size, mitral regurgitation grade, type of surgery, systemic markers of inflammation or presence of diabetes or hypertension. Most of CD68-KP1+ cells corresponded to dendritic cell population based on their morphology and immunoreactivity for DC-SIGN. The numbers of mast cells and CD20+ B-lymphocytes did not differ between AF and SR patients. No foci of inflammation were detected in any sample.An immunohistochemical analysis of samples from patients undergoing open heart surgery showed moderate and site-specific increase of inflammatory cells in the atrial myocardium of patients with AF compared to those in SR, with prevailing population of monocyte-macrophage lineage. These cells and their cytokine products may play a role in atrial remodeling and AF persistence.

  10. Noninvasive Imaging of Human Atrial Activation during Atrial Flutter and Normal Rhythm from Body Surface Potential Maps.

    Science.gov (United States)

    Zhou, Zhaoye; Jin, Qi; Yu, Long; Wu, Liqun; He, Bin

    2016-01-01

    Knowledge of atrial electrophysiological properties is crucial for clinical intervention of atrial arrhythmias and the investigation of the underlying mechanism. This study aims to evaluate the feasibility of a novel noninvasive cardiac electrical imaging technique in imaging bi-atrial activation sequences from body surface potential maps (BSPMs). The study includes 7 subjects, with 3 atrial flutter patients, and 4 healthy subjects with normal atrial activations. The subject-specific heart-torso geometries were obtained from MRI/CT images. The equivalent current densities were reconstructed from 208-channel BSPMs by solving the inverse problem using individual heart-torso geometry models. The activation times were estimated from the time instant corresponding to the highest peak in the time course of the equivalent current densities. To evaluate the performance, a total of 32 cycles of atrial flutter were analyzed. The imaged activation maps obtained from single beats were compared with the average maps and the activation maps measured from CARTO, by using correlation coefficient (CC) and relative error (RE). The cardiac electrical imaging technique is capable of imaging both focal and reentrant activations. The imaged activation maps for normal atrial activations are consistent with findings from isolated human hearts. Activation maps for isthmus-dependent counterclockwise reentry were reconstructed on three patients with typical atrial flutter. The method was capable of imaging macro counterclockwise reentrant loop in the right atrium and showed inter-atria electrical conduction through coronary sinus. The imaged activation sequences obtained from single beats showed good correlation with both the average activation maps (CC = 0.91±0.03, RE = 0.29±0.05) and the clinical endocardial findings using CARTO (CC = 0.70±0.04, RE = 0.42±0.05). The noninvasive cardiac electrical imaging technique is able to reconstruct complex atrial reentrant activations and focal

  11. Prevention of atrial fibrillation by inter-atrial septum pacing guided by electrophysiological testing, in patients with delayed interatrial conduction.

    Science.gov (United States)

    Manolis, A G; Katsivas, A G; Vassilopoulos, C; Koutsogeorgis, D; Louvros, N E

    2002-04-01

    Interatrial septum (IAS) pacing seems efficient in synchronizing atrial depolarization in patients (pts) with delayed inter-atrial conduction, but its clinical role in preventing atrial tachyarrhythmias is still debated. This study was conducted in order to evaluate the clinical efficacy of IAS pacing guided by pace mapping of the IAS, as an alternative treatment modality in pts with drug refractory paroxysmal atrial fibrillation (PAF). We evaluated 29 pts (13 male, 16 female, 60 +/- 11 years), with drug refractory PAF, normal sinus node function and prolonged inter-atrial conduction time (P wave 142 +/- 10 ms). Multipolar catheters were inserted and the electrograms from the high right atrium (HRA) and proximal, middle and distal coronary sinus (CS) were recorded. The IAS was paced from multiple sites. The site of IAS where the timing between HRA and distal CS was AAIR (75-140 bpm) mode, with random selection of the order and after discontinuation of antiarrhythmic treatment. During the fourth period, the same AAIR mode was assessed, but antiarrhythmic drugs were also administered. We compared the arrhythmia free interval among the four periods. The proportion of atrial paced beats in AAIR pacing mode plus antiarrhythmics was significantly higher compared with the drug-free period in AAIR mode (57 +/- 9% and 49 +/- 9% respectively, P=0017) and with AAT pacing mode (44 +/- 10%,(, PAAIR mode. These intervals did not differ significantly from the pre-implantation period (24.1 +/- 6.3 days). The arrhythmia free interval in AAIR pacing in combination with antiarrhythmic drug therapy was 38.7 +/- 8.1 days and this was significantly longer than the previous periods (P<0.05). Atrial septal pacing in combination with antiarrhythmic drug therapy reduced the incidence of PAF in pts with prolonged inter-atrial conduction times. Pace mapping of the IAS is an attractive technique to assess the shortest atrial activation time between HRA and distal CS. Whether placement of the

  12. Arrhythmia

    Science.gov (United States)

    ... Activities Obesity, Nutrition, and Physical Activity Population and Epidemiology Studies Women’s Health All Science A-Z Grants & ... this surgery, a surgeon makes small cuts or burns in the atria. These cuts or burns prevent ...

  13. Arrhythmia

    Science.gov (United States)

    ... with your heart. Examples include heart disease and congenital heart disease.Ventricular tachycardia and ventricular fibrillation: The heart beats too fast and may not pump enough These types are severe and require immediate treatment. SymptomsSymptoms of ...

  14. Arrhythmias

    Science.gov (United States)

    ... operated device implanted into the body (near the collarbone) through a surgical procedure. Connected to the heart ... defibrillator (ICD) is surgically placed near the left collarbone. Wires run from the defibrillator to the heart. ...

  15. Arrhythmia

    Science.gov (United States)

    ... a type of v-fib that causes a unique pattern on an EKG (electrocardiogram) test. Certain medicines ... and peas. A healthy diet is low in sodium (salt), added sugars, solid fats, and refined grains. ...

  16. Arrhythmias

    Science.gov (United States)

    ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ... the principles of the Health on the Net Foundation (www.hon.ch). The information provided herein should ...

  17. Genetics of Inherited Arrhythmias in Children

    Directory of Open Access Journals (Sweden)

    Maully J. Shah

    2008-05-01

    Full Text Available Over the past two decades, breakthroughs in basic science have revealed the genetic etiology for several inherited arrhythmias. Onset of arrhythmias often commences in childhood and adolescence. The aim of the article is to provide a succinct overview of the genetic background of diseases that may cause life threatening arrhythmias in children and provide a description of reported genotype-phenotype relationships. Inherited channelopathies, namely, those causing long QT syndrome, short QT syndrome, catecholamine sensitive ventricular polymorphic ventricular tachycardia and Brugada syndrome and two cardiomyopathies (hypertrophic and arrhythmogenic right ventricular dysplasia associated with ventricular arrhythmias are discussed.

  18. New Procedure for Treatment of Atrial Fibrillation in Patients with Valvular Heart Disease

    Directory of Open Access Journals (Sweden)

    Naser Safaie

    2010-09-01

    Full Text Available "nPatients with valvular heart disease suffer from atrial fibrillation for more than 12 months after valve surgery and have a low probability of remaining in sinus rhythm. We performed an intra-operative procedure similar to surgical maze ІІІ procedure for conversion of this arrhythmia to sinus rhythm. We did this study to evaluate the efficacy of this procedure to restore the sinus rhythm in patients with valvular heart disease. 28 patients with valvular heart disease and chronic persistent atrial fibrillation underwent different combinations of valve surgery and concomitant reduction of left and right atrial size and resection of both atrial auricles in Shahid Madani cardiothoracic center from September 2004 to October 2008. The procedure for atrial fibrillation treatment was performed with cardiopulmonary bypass and after mitral valve replacement. There was one in-hospital death postoperatively because of respiratory failure, but no other complication till 6 months after the operation. Out of 28 patients, 23 were in sinus rhythm one week after the operation, one patient had junctional rhythm after the operation that restored to sinus rhythm and 4 patients had persistent atrial fibrillation. During the 12-month follow up, atrial fibrillation was corrected in 82.14%. Doppler echocardiography in these patients with sinus rhythm demonstrated good atrial contractility. This procedure on both atria is effective and less invasive than the original maze procedure to eliminate the atrial fibrillation, and can be performed in patients with valvular heart disease without increasing the risk of operation.

  19. Efficacy of Short-Term Antiarrhythmic Drugs Use after Catheter Ablation of Atrial Fibrillation-A Systematic Review with Meta-Analyses and Trial Sequential Analyses of Randomized Controlled Trials.

    Science.gov (United States)

    Chen, Weijie; Liu, Hang; Ling, Zhiyu; Xu, Yanping; Fan, Jinqi; Du, Huaan; Xiao, Peilin; Su, Li; Liu, Zengzhang; Lan, Xianbin; Zrenner, Bernhard; Yin, Yuehui

    2016-01-01

    The efficacy of short-term antiarrhythmic drugs (AADs) use compared with no-AADs prescription after catheter ablation of atrial fibrillation (AF) in preventing atrial arrhythmia recurrence is uncertain. We searched PubMed, Embase, and the Cochrane Library through December 2015 to identify randomized controlled trials (RCTs) which evaluated the efficacy of short-term AADs use compared with no-AADs prescription after AF ablation in preventing atrial arrhythmia recurrence. The primary outcome was labeled as early atrial arrhythmia recurrence within 3 months after ablation. Secondary outcome was defined as late recurrence after 3 months of ablation. Random-effects model or fixed-effects model was used to estimate relative risks (RRs) with 95% confidence intervals (CIs). Six RCTs with 2,667 patients were included into this meta-analysis. Compared with no-AADs administration after AF ablation, short-term AADs use was associated with significant reduction of early atrial arrhythmia recurrence (RR, 0.68; 95% CI, 0.52-0.87; p = 0.003). Trial sequential analysis (TSA) showed that the cumulative Z-curve crossed the trial sequential monitoring boundary for benefit, establishing sufficient and conclusive evidence. However, compared with no-AADs prescription, short-term AADs use after AF ablation didn't significantly reduce the risk of late atrial arrhythmia recurrence (RR, 0.92; 95% CI, 0.83-1.03; p = 0.15). TSA supported this result; meanwhile the estimated required information size (1,486 patients) was also met. Short-term use of AADs after AF ablation can significantly decrease the risk of early atrial arrhythmia recurrence but not lead to corresponding reduction in risk of late atrial arrhythmia recurrence.

  20. Dynamic triggering

    Science.gov (United States)

    Hill, David P.; Prejean, Stephanie; Schubert, Gerald

    2015-01-01

    Dynamic stresses propagating as seismic waves from large earthquakes trigger a spectrum of responses at global distances. In addition to locally triggered earthquakes in a variety of tectonic environments, dynamic stresses trigger tectonic (nonvolcanic) tremor in the brittle–plastic transition zone along major plate-boundary faults, activity changes in hydrothermal and volcanic systems, and, in hydrologic domains, changes in spring discharge, water well levels, soil liquefaction, and the eruption of mud volcanoes. Surface waves with periods of 15–200 s are the most effective triggering agents; body-wave trigger is less frequent. Triggering dynamic stresses can be < 1 kPa.

  1. Electromechanical wave imaging for arrhythmias

    Science.gov (United States)

    Provost, Jean; Thanh-Hieu Nguyen, Vu; Legrand, Diégo; Okrasinski, Stan; Costet, Alexandre; Gambhir, Alok; Garan, Hasan; Konofagou, Elisa E.

    2011-11-01

    Electromechanical wave imaging (EWI) is a novel ultrasound-based imaging modality for mapping of the electromechanical wave (EW), i.e. the transient deformations occurring in immediate response to the electrical activation. The correlation between the EW and the electrical activation has been established in prior studies. However, the methods used previously to map the EW required the reconstruction of images over multiple cardiac cycles, precluding the application of EWI for non-periodic arrhythmias such as fibrillation. In this study, new imaging sequences are developed and applied based on flash- and wide-beam emissions to image the entire heart at very high frame rates (2000 fps) during free breathing in a single heartbeat. The methods are first validated by imaging the heart of an open-chest canine while simultaneously mapping the electrical activation using a 64-electrode basket catheter. Feasibility is then assessed by imaging the atria and ventricles of closed-chest, conscious canines during sinus rhythm and during right-ventricular pacing following atrio-ventricular dissociation, i.e., during a non-periodic rhythm. The EW was validated against electrode measurements in the open-chest case, and followed the expected electrical propagation pattern in the closed-chest setting. These results indicate that EWI can be used for the characterization of non-periodic arrhythmias in conditions similar to the clinical setting, in a single heartbeat, and during free breathing.

  2. Comparison of Atrial Fibrillation in the Young versus That in the Elderly: A Review

    Directory of Open Access Journals (Sweden)

    Rajiv Sankaranarayanan

    2013-01-01

    Full Text Available The incidence and prevalence of atrial fibrillation (AF are projected to increase significantly worldwide, imposing a significant burden on healthcare resources. The disease itself is extremely heterogeneous in its epidemiology, pathophysiology, and treatment options based on individual patient characteristics. Whilst ageing is well recognised to be an independent risk factor for the development of AF, this condition also affects the young in whom the condition is frequently symptomatic and troublesome. Traditional thinking suggests that the causal factors and pathogenesis of the condition in the young with structurally normal atria but electrophysiological “triggers” in the form of pulmonary vein ectopics leading to lone AF are in stark contrast to that in the elderly who have AF primarily due to an abnormal substrate consisting of fibrosed and dilated atria acting in concert with the pulmonary vein triggers. However, there can be exceptions to this rule as there is increasing evidence of structural and electrophysiological abnormalities in the atrial substrate in young patients with “lone AF,” as well as elderly patients who present with idiopathic AF. These reports seem to be blurring the distinction in the pathophysiology of so-called idiopathic lone AF in the young versus that in the elderly. Moreover with availability of improved and modern investigational and diagnostic techniques, novel causes of AF are being reported thereby seemingly consigning the diagnosis of “lone AF” to a rather mythical existence. We shall also elucidate in this paper the differences seen in the epidemiology, causes, pathogenesis, and clinical features of AF in the young versus that seen in the elderly, thereby requiring clearly defined management strategies to tackle this arrhythmia and its associated consequences.

  3. Deglutition induced atrial tachycardia and atrial fibrillation.

    Science.gov (United States)

    Kanjwal, Yousuf; Imran, Naser; Grubb, Blair

    2007-12-01

    Deglutition induced supraventricular tachycardia is an uncommon condition postulated to be a vagally mediated phenomenon due to mechanical stimulation. Patients usually present with mild symptoms or may have severe debilitating symptoms. Treatment with Class I agents, beta blockers, calcium channel blockers, amiodarone and radiofrquency catheter ablation has shown to be successful in the majority of reported cases. We report the case of a 46-year-old healthy woman presenting with palpitations on swallowing that was documented to be transient atrial tachycardia with aberrant ventricular conduction as well as transient atrial fibrillation. She was successfully treated with propafenone with no induction of swallowing-induced tachycardia after treatment. This is also the first case to show swallowing-induced atrial tachycardia and atrial fibrillation in the same patient.

  4. Ablation of supraventricular arrhythmias in adult congenital heart disease: A contemporary review.

    Science.gov (United States)

    Combes, Nicolas; Derval, Nicolas; Hascoët, Sebastien; Zhao, Alexandre; Amet, Denis; Le Bloa, Mathieu; Maltret, Alice; Heitz, François; Thambo, Jean-Benoit; Marijon, Eloi

    2017-05-01

    Supraventricular arrhythmias are an important and increasing cause of morbidity in adults with congenital heart disease, requiring specific management strategies. Pharmacological treatment has limited efficacy, and is often associated with some side-effects. Major improvements in catheter ablation techniques have opened new opportunities to better understand underlying mechanisms of supraventricular arrhythmias, offer better therapy, and eventually improve symptoms and quality of life in these patients. An array of tools and techniques are necessary to access relevant anatomical areas to address the arrhythmogenic substrate. The mechanism of these arrhythmias is mostly related to macroreentry around surgical scars or cavotricuspid isthmus-dependent flutter. The efficacy of catheter ablation is mainly dependent on the underlying congenital heart condition, with the most complex cases typically being associated with atrial switch and Fontan surgeries. Although relatively high rates of recurrence are seen after a single procedure, additional attempts are often helpful to decrease recurrences and improve symptoms. Catheter ablation in such patients continues to present many unique challenges that are best addressed by experienced multidisciplinary teams, at centres equipped with the proper catheters, imaging capabilities, mapping systems and support staff needed to maximize safety and success. Consensus indications have emerged that often support ablation as first-line therapy in these patients. In this comprehensive review, we aim to describe the specific issues associated with ablation of supraventricular arrhythmias in adult congenital heart disease, assess the results in contemporary practice and, finally, review the current indications. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. The Wolff-Parkinson-White electrocardiogram pattern in athletes: how and when to evaluate the risk for dangerous arrhythmias. The opinion of the paediatric cardiologist.

    Science.gov (United States)

    Sarubbi, Berardo

    2006-04-01

    Although diagnostic assessment and treatment have been described in detail in patients with symptomatic Wolff-Parkinson-White (WPW) syndrome, the management of asymptomatic subjects remains controversial. Usually they are assumed to have a benign prognosis, although they do very occasionally present with ventricular fibrillation (VF) as the first manifestation of the syndrome. Discovering a WPW pattern in a previously asymptomatic athlete on a routine electrocardiogram (ECG) identifies the necessity for more accurate screening tests. However, non-invasive methods (Holter monitoring, exercise treadmill testing) seem to be relatively incomplete for risk stratification, especially for athletes. Current guidelines do not always recommend a routine electrophysiological study (EPS) in patients with an asymptomatic WPW ECG pattern, especially in children younger than 12 years. Individuals who engage in high-risk occupations or those patients who have a pre-excitation pattern which precludes them from following their chosen career or activities may be exceptions. The presence of inducible reciprocating tachycardia during EPS, especially when it triggers atrial fibrillation with short RR interval, can represent a specific risk marker of dangerous arrhythmias.

  6. Management of common arrhythmias: Part II. Ventricular arrhythmias and arrhythmias in special populations.

    Science.gov (United States)

    Hebbar, A Kesh; Hueston, William J

    2002-06-15

    In patients without established cardiac disease, the occurrence of premature ventricular complexes without sustained ventricular tachycardia is more an annoyance than a medical risk, and treatment is not required. In contrast, patients with established heart disease and premature ventricular complexes have a higher likelihood of developing ventricular tachycardia or fibrillation. These patients should be treated with a beta blocker or class I antiarrhythmic drug. Treatment of arrhythmias in pregnant women is rarely needed. When treatment is required, amiodarone should be avoided, and beta blockers should be used with caution, because these agents have been associated with fetal growth retardation. The most important rhythm abnormality in athletes is ventricular tachycardia associated with hypertrophic cardiomyopathy. If the presence of the disease is confirmed by echocardiography, beta-blocker therapy is necessary, and these patients should be limited to participation in nonstrenuous sports. Acute arrhythmias in children with Wolff-Parkinson-White syndrome can be treated with adenosine. Radiofrequency ablation of the accessory pathway can provide long-term control.

  7. A three-dimensional human atrial model with fiber orientation. Electrograms and arrhythmic activation patterns relationship.

    Directory of Open Access Journals (Sweden)

    Catalina Tobón

    Full Text Available The most common sustained cardiac arrhythmias in humans are atrial tachyarrhythmias, mainly atrial fibrillation. Areas of complex fractionated atrial electrograms and high dominant frequency have been proposed as critical regions for maintaining atrial fibrillation; however, there is a paucity of data on the relationship between the characteristics of electrograms and the propagation pattern underlying them. In this study, a realistic 3D computer model of the human atria has been developed to investigate this relationship. The model includes a realistic geometry with fiber orientation, anisotropic conductivity and electrophysiological heterogeneity. We simulated different tachyarrhythmic episodes applying both transient and continuous ectopic activity. Electrograms and their dominant frequency and organization index values were calculated over the entire atrial surface. Our simulations show electrograms with simple potentials, with little or no cycle length variations, narrow frequency peaks and high organization index values during stable and regular activity as the observed in atrial flutter, atrial tachycardia (except in areas of conduction block and in areas closer to ectopic activity during focal atrial fibrillation. By contrast, cycle length variations and polymorphic electrograms with single, double and fragmented potentials were observed in areas of irregular and unstable activity during atrial fibrillation episodes. Our results also show: (1 electrograms with potentials without negative deflection related to spiral or curved wavefronts that pass over the recording point and move away, (2 potentials with a much greater proportion of positive deflection than negative in areas of wave collisions, (3 double potentials related with wave fragmentations or blocking lines and (4 fragmented electrograms associated with pivot points. Our model is the first human atrial model with realistic fiber orientation used to investigate the relationship

  8. Evaluation and Management of Maternal Cardiac Arrhythmias.

    Science.gov (United States)

    Metz, Torri D; Khanna, Amber

    2016-12-01

    Pregnant women often complain of palpitations. The differential diagnosis for new-onset palpitations in pregnancy ranges from benign conditions to life-threatening arrhythmias. Maternal arrhythmias can occur in isolation or in the setting of underlying structural heart disease. Optimal management of maternal cardiac arrhythmias includes identification of the specific arrhythmia, diagnosis of comorbid conditions, and appropriate intervention. In general, management of maternal cardiac arrhythmias is similar to that of the general population. Special consideration must be given as to the effects of medications and procedures on both the mother and fetus to optimize outcomes. The importance of multidisciplinary care with cardiology, obstetrics, and anesthesia is emphasized. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Arrhythmia and Sudden Death in Hemodialysis Patients: Protocol and Baseline Characteristics of the Monitoring in Dialysis Study.

    Science.gov (United States)

    Charytan, David M; Foley, Robert; McCullough, Peter A; Rogers, John D; Zimetbaum, Peter; Herzog, Charles A; Tumlin, James A

    2016-04-07

    Dialysis patients have high rates of cardiovascular morbidity and mortality, but data on arrhythmia burden, arrhythmia type, arrhythmia triggers, and the identity of terminal arrhythmias have historically been limited by an inability to monitor heart rhythm for prolonged periods. To investigate arrhythmia and its association with sudden death in dialysis-dependent ESRD, describe the potential for implantable devices to advance study of dialysis physiology, review the ethical implications of using implantable devices in clinical studies, and report on the protocol and baseline results of the Monitoring in Dialysis Study (MiD). In this multicenter, interventional-observational, prospective cohort study, we placed implantable loop recorders in patients undergoing long-term hemodialysis. The proportion of patients experiencing clinically significant arrhythmias was the primary endpoint. For 6 months, we captured detailed data on the primary endpoint, symptomatic arrhythmias, other electrocardiographic variables, dialysis prescription, electrolytes, dialysis-related variables, and vital signs. We collected additional electrocardiographic data for up to 1 year. Overall, 66 patients underwent implantation in sites in the United States and India. Diabetes was present in 63.6% of patients, 12.1% were age ≥70 years, 69.7% were men, and 53.0% were black. Primary and secondary endpoint data are expected in 2016. Cardiac arrhythmia is an important contributor to cardiovascular morbidity and mortality in dialysis patients, but available technology has previously limited the ability to estimate its true burden and triggers and to define terminal rhythms in sudden death. Use of implantable technology in observational studies raises complex issues but may greatly expand understanding of dialysis physiology. The use of implantable loop recorders in MiD is among the first examples of such a trial, and the results are expected to provide novel insights into the nature of arrhythmia

  10. Cryoablation for treatment of cardiac arrhythmias: results of the European Heart Rhythm Association survey.

    Science.gov (United States)

    Chen, Jian; Lenarczyk, Radoslaw; Boveda, Serge; Richard Tilz, Roland; Hernandez-Madrid, Antonio; Ptaszynski, Pawel; Pudulis, Janis; Dagres, Nikolaos

    2017-02-01

    The purpose of this survey was to assess the current practice in Europe regarding cryoablation for treatment of different cardiac arrhythmias. The data are based on an electronic questionnaire sent to members of the European Heart Rhythm Association Research Network. Responses were received from 49 centres in 18 countries. The results show that cryoablation for supraventricular tachycardia in European centres is an alternative to radiofrequency ablation, which is in accordance with guidelines. There is reasonable consensus regarding clinical results and complications of cryoablation procedure. Some inter-centre variability with respect to patient selection and ablation strategy in cryoablation of atrial fibrillation was demonstrated, underscoring the need for further research.

  11. Isolation of the posterior left atrium for patients with persistent atrial fibrillation: routine adenosine challenge for dormant posterior left atrial conduction improves long-term outcome.

    Science.gov (United States)

    McLellan, Alex J A; Prabhu, Sandeep; Voskoboinik, Alex; Wong, Michael C G; Walters, Tomos E; Pathik, Bhupesh; Morris, Gwilym M; Nisbet, Ashley; Lee, Geoffrey; Morton, Joseph B; Kalman, Jonathan M; Kistler, Peter M

    2017-12-01

    Catheter ablation to achieve posterior left atrial wall (PW) isolation may be performed as an adjunct to pulmonary vein isolation (PVI) in patients with persistent atrial fibrillation (AF). We aimed to determine whether routine adenosine challenge for dormant posterior wall conduction improved long-term outcome. A total of 161 patients with persistent AF (mean age 59 ± 9 years, AF duration 6 ± 5 years) underwent catheter ablation involving circumferential PVI followed by PW isolation. Posterior left atrial wall isolation was performed with a roof and inferior wall line with the endpoint of bidirectional block. In 54 patients, adenosine 15 mg was sequentially administered to assess reconnection of the pulmonary veins and PW. Sites of transient reconnection were ablated and adenosine was repeated until no further reconnection was present. Holter monitoring was performed at 6 and 12 months to assess for arrhythmia recurrence. Posterior left atrial wall isolation was successfully achieved in 91% of 161 patients (procedure duration 191 ± 49 min, mean RF time 40 ± 19 min). Adenosine-induced reconnection of the PW was demonstrated in 17%. The single procedure freedom from recurrent atrial arrhythmia was superior in the adenosine challenge group (65%) vs. no adenosine challenge (40%, P conduction was associated with an improvement in the success of catheter ablation for persistent AF.

  12. TASK-1 Channels May Modulate Action Potential Duration of Human Atrial Cardiomyocytes

    Science.gov (United States)

    Limberg, Sven H.; Netter, Michael F.; Rolfes, Caroline; Rinné, Susanne; Schlichthörl, Günter; Zuzarte, Marylou; Vassiliou, Timon; Moosdorf, Rainer; Wulf, Hinnerk; Daut, Jürgen; Sachse, Frank B.; Decher, Niels

    2011-01-01

    Background/Aims: Atrial fibrillation is the most common arrhythmia in the elderly, and potassium channels with atrium-specific expression have been discussed as targets to treat atrial fibrillation. Our aim was to characterize TASK-1 channels in human heart and to functionally describe the role of the atrial whole cell current ITASK-1. Methods and Results: Using quantitative PCR, we show that TASK-1 is predominantly expressed in the atria, auricles and atrio-ventricular node of the human heart. Single channel recordings show the functional expression of TASK-1 in right human auricles. In addition, we describe for the first time the whole cell current carried by TASK-1 channels (ITASK-1) in human atrial tissue. We show that ITASK-1 contributes to the sustained outward current IKsus and that ITASK-1 is a major component of the background conductance in human atrial cardiomyocytes. Using patch clamp recordings and mathematical modeling of action potentials, we demonstrate that modulation of ITASK-1 can alter human atrial action potential duration. Conclusion: Due to the lack of ventricular expression and the ability to alter human atrial action potential duration, TASK-1 might be a drug target for the treatment of atrial fibrillation. PMID:22178873

  13. Prenatal features of Costello syndrome: Ultrasonographic findings and atrial tachycardia

    Science.gov (United States)

    Lin, Angela E.; O’Brien, Barbara; Demmer, Laurie A.; Almeda, Kristina K.; Blanco, Cynthia L.; Glasow, Patrick F.; Berul, Charles I.; Hamilton, Robert; Innes, A. Micheil; Lauzon, Julie L.; Sol-Church, Katia; Gripp, Karen W.

    2015-01-01

    Objective Delineate prenatal features of Costello syndrome (caused by HRAS mutations) which consists of mental retardation, facial, cardiovascular, skin, and musculoskeletal anomalies, and tumor predisposition. Methods Literature and new cases classified as Group I (pre-HRAS), Group II (HRAS confirmed), and Group III (HRAS confirmed in natural history study, plus three contributed cases). Results Polyhydramnios occurred in most (mean 79%) pregnancies of cases in Groups I (98), II (107), and III (17), advanced paternal age and prematurity were noted in approximately half. Less frequent were nuchal thickening, ascites, shortened long bones, abnormal hand posture, ventriculomegaly, macrosomia, and macrocephaly. Fetal arrhythmia occurred in 9 cases (6 supraventricular or unspecified tachycardia, 1 unspecified arrhythmia, 2 premature atrial contractions, PACs); excluding 3 new cases and 2 with PACs, the estimated prenatal frequency is 4/222 (2%). Conclusion Costello syndrome can be suspected prenatally when polyhydramnios is accompanied by nuchal thickening, hydrops, shortened long bones, abnormal hand posture, ventriculomegaly, large size, and macrocephaly, and especially fetal atrial tachycardia. Consideration should be given for timely prenatal diagnostic studies for confirmative HRAS gene mutations, and for maternal treatment of serious fetal arrhythmia. PMID:19382114

  14. Supraventricular arrhythmias in patients with cardiac sarcoidosis prevalence, predictors, and clinical implications.

    Science.gov (United States)

    Viles-Gonzalez, Juan F; Pastori, Luciano; Fischer, Avi; Wisnivesky, Juan P; Goldman, Martin G; Mehta, Davendra

    2013-04-01

    Cardiac sarcoidosis (CS) is known to be associated with congestive heart failure, conduction disorders, and tachyarrhythmias. Ventricular arrhythmias are the most feared cardiac manifestation because they often are unpredictable, may be the fi rst manifestation of the disease, and may be fatal. The propensity for the development of supraventricular arrhythmias (SVAs) in patients with CS has not been described. The aim of this study was to assess the prevalence as well as the predictors of SVA. We retrospectively investigated 100 patients with biopsy specimen-proven systemic sarcoidosis and evidence of cardiac involvement (defi ned by cardiac biopsy specimen, PET scan, or cardiac MRI). The mean follow-up was 5.8 3.6 years. ECG, Holter monitoring, implantable cardioverter defibrillator interrogations, or electrophysiology studies were used to document SVA. Echocardiographic data, demographics, and extracardiac involvement were recorded, and univariate and Poisson regressions were performed to compare characteristics of patients with and without documented SVA. The prevalence of SVA was 32%, and atrial fibrillation was the most common arrhythmia, comprising 18% of the total burden, followed by atrial tachycardias (7%), atrial fl utter (5%), and other supraventricular tachycardias (2%). Of the patients with SVA, 96% were symptomatic. Left atrial enlargement (LAE) was more frequent in the group with SVA, with an incidence of 267.8 per 1,000 person-years, and it significantly increased the likelihood of SVA on multivariate analysis (risk ratio, 6.12; 95% CI, 2.19-17.11). Diastolic dysfunction, systemic hypertension, and right atrial enlargement were predictors of SVA on univariate analysis. Left ventricular hypertrophy, right ventricular dysfunction, tricuspid valve disease, pulmonary hypertension, and pulmonary sarcoidosis were not associated with SVA on univariate analysis. The study systematically evaluated the frequency of SVA in a large number of patients with CS

  15. [New antiarrhythmic drugs for the treatment of atrial fibrillation].

    Science.gov (United States)

    Botto, Giovanni Luca; Russo, Giovanni; Mariconti, Barbara; Pentimalli, Francesco; Campana, Carlo

    2012-10-01

    Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and a difficult-to-treat arrhythmia. Conventional antiarrhythmic drugs, including flecainide, propafenone, sotalol and amiodarone, have several limitations in terms of efficacy and tolerability, and have made new drug development crucial. In the last decade, intensive research was undertaken to find new pharmacological options for the treatment of AF, and two new drugs are now available. Vernakalant is an atrial-selective drug specifically designed to block sodium channels at the atrial level, and its intravenous formulation has recently been recommended for approval by the Food and Drug Administration for pharmacological conversion of AF. Dronedarone is a chemical derivative of amiodarone (though having a significantly different clinical profile) with effects on multiple ion channels that proved effective in reducing the rate of the combined endpoint of death from any cause and cardiovascular hospitalization in patients with non-permanent AF enrolled in the ATHENA study. The available evidence on the efficacy of dronedarone has led to approval for recommendation in many clinical situations in which rhythm control is desirable. The complexity of the mechanisms underlying AF and the large variability of associated comorbidities render the AF patient a unique entity, making the identification of patients who may benefit from these novel approaches challenging.

  16. Radiofrequency catheter ablation in patients with symptomatic atrial flutter/tachycardia after orthotopic heart transplantation.

    Science.gov (United States)

    Li, Yi-gang; Grönefeld, Gerian; Israel, Carsten; Lu, Shang-biao; Wang, Qun-shan; Hohnloser, Stefan H

    2006-12-20

    Atrial tachycardia or flutter is common in patients after orthotopic heart transplantation. Radiofrequency catheter ablation to treat this arrhythmia has not been well defined in this setting. This study was conducted to assess the incidence of various symptomatic atrial arrhythmias and the efficacy and safety of radiofrequency catheter ablation in these patients. Electrophysiological study and catheter ablation were performed in patients with symptomatic tachyarrhythmia. One Halo catheter with 20 poles was positioned around the tricuspid annulus of the donor right atrium, or positioned around the surgical anastomosis when it is necessary. Three quadripolar electrode catheters were inserted via the right or left femoral vein and positioned in the recipient atrium, the bundle of His position, the coronary sinus. Programmed atrial stimulation and burst pacing were performed to prove electrical conduction between the recipient and the donor atria and to induce atrial arrhythmias. Out of 55 consecutive heart transplantation patients, 6 males [(58 +/- 12) years] developed symptomatic tachycardias at a mean of (5 +/- 4) years after heart transplantation. Electrical propagation through the suture line between the recipient and the donor atrium was demonstrated during atrial flutter or during recipient atrium and donor atrium pacing in 2 patients. By mapping around the suture line, the earliest fragmented electrogram of donor atrium was assessed. This electrical connection was successfully ablated in the anterior lateral atrium in both patients. There was no electrical propagation through the suture line in the other 4 patients. Two had typical atrial flutter in the donor atrium which was successfully ablated by completing a linear ablation between the tricuspid annulus and the inferior vena cava. Two patients had atrial tachycardia which was ablated in the anterior septal and lateral donor atrium. There were no procedure-related complications. Patients were free of

  17. Antiarrhythmics after ablation of atrial fibrillation (5A Study): six-month follow-up study.

    Science.gov (United States)

    Leong-Sit, Peter; Roux, Jean-Francois; Zado, Erica; Callans, David J; Garcia, Fermin; Lin, David; Marchlinski, Francis E; Bala, Rupa; Dixit, Sanjay; Riley, Michael; Hutchinson, Mathew D; Cooper, Joshua; Russo, Andrea M; Verdino, Ralph; Gerstenfeld, Edward P

    2011-02-01

    We previously demonstrated that treatment with antiarrhythmic drugs (AADs) during the first 6 weeks after atrial fibrillation (AF) ablation reduces the incidence of clinically significant atrial arrhythmias and need for cardioversion or hospitalization for arrhythmia management. Whether early rhythm suppression decreases longer-term arrhythmia recurrence is unknown. We now report the 6-month follow-up data from this study. The Antiarrhythmics After Ablation of Atrial Fibrillation study prospectively randomized patients with paroxysmal AF undergoing ablation to either receive (AAD group) or not receive (no-AAD group) AAD treatment for the first 6 weeks after ablation; all patients received atrioventricular nodal blockers. Physicians were encouraged to stop the AADs after the 6-week treatment period. All patients underwent 4 weeks of transtelephonic monitoring to document asymptomatic AF and an evaluation at 6 weeks and 6 months. A total of 110 patients (71% men) aged 55±9 years were randomized, with 53 to AAD and 57 to no AAD. At 6 months, there was no difference in freedom from AF between the early AAD and no-AAD groups (38/53 [72%] versus 39/57 [68%]; P=0.84). Lack of early AF recurrence during the initial 6-week period was the only independent predictor of 6-month freedom from AF (64/76 [84%] without early recurrence versus 13/34 [38%] with early recurrence; P=0.0001). Although short-term use of AADs after AF ablation decreases early recurrence of atrial arrhythmias, early use of AADs does not prevent arrhythmia recurrence at 6 months. Early AF recurrence on or off AADs during the initial 6-week blanking period is a strong independent predictor of long-term AF recurrence.

  18. Clinical application of arrhythmia analyzer in ICU.

    Science.gov (United States)

    Oyama, T; Ishihara, H; Tanioka, F; Matsuki, A; Aida, N; Ishii, H

    1987-01-01

    A microcomputer system (NEC Sanei Ins. Company Ltd.) has been developed for the continuous monitoring and storage and retrieval of data from serial ECG tracings in each ICU patient. Eight hundred and forty patients were monitored using the system. Diagnosis of ventricular arrhythmias and ST-segment change was highly accurate. However, the false positive diagnosis was sometimes generated by artifact. Diagnosis of supraventricular arrhythmias or rhythmic abnormalities were less accurate compared with that of ventricular arrhythmias. Application of microcomputer system in the space limited ICU is of benefit to identify and evaluate ECG gracings in time saving way. However, further version-up is needed to promote the accuracy of the diagnosis.

  19. Imidazoline receptors in the heart: a novel target and a novel mechanism of action that involves atrial natriuretic peptides

    OpenAIRE

    S. Mukaddam-Daher; J. Gutkowska

    2004-01-01

    Chronic stimulation of sympathetic nervous activity contributes to the development and maintenance of hypertension, leading to left ventricular hypertrophy (LVH), arrhythmias and cardiac death. Moxonidine, an imidazoline antihypertensive compound that preferentially activates imidazoline receptors in brainstem rostroventrolateral medulla, suppresses sympathetic activation and reverses LVH. We have identified imidazoline receptors in the heart atria and ventricles, and shown that atrial I1-rec...

  20. Gain-of-function mutations in potassium channel subunit KCNE2 associated with early-onset lone atrial fibrillation

    DEFF Research Database (Denmark)

    Nielsen, Jonas Bille; Bentzen, Bo Hjorth; Olesen, Morten Salling

    2014-01-01

    Aims: Atrial fibrillation (AF) is the most common cardiac arrhythmia. Disturbances in cardiac potassium conductance are considered as one of the disease mechanisms in AF. We aimed to investigate if mutations in potassium-channel β-subunits KCNE2 and KCNE3 are associated with early-onset lone AF. ...

  1. Amiodarone after surgical ablation for atrial fibrillation: Is it really necessary? A prospective randomized controlled trial.

    Science.gov (United States)

    Ad, Niv; Holmes, Sari D; Shuman, Deborah J; Pritchard, Graciela; Miller, Casey E

    2016-03-01

    Prophylactic antiarrhythmic drug (AAD) treatment is a well-established practice after catheter ablation for atrial fibrillation (AF), but it is controversial after surgical ablation. This prospective randomized controlled trial examined whether amiodarone after surgical ablation reduced atrial arrhythmia recurrence within the first 3 months after surgery. Ninety patients were randomized to receive (n = 45) or not receive (n = 45) amiodarone after surgical ablation. Rhythm status was ascertained via clinical follow-up and 72-hour continuous monitoring at 6 and 12 weeks, using Heart Rhythm Society guidelines. Primary outcome was defined as atrial arrhythmia recurrence, cardioversion, ablation, or crossover from no-amiodarone to amiodarone as a result of atrial arrhythmia during follow-up. An intention-to-treat approach was used. The 2 study groups were similar in traditional predictors for failure, including left atrium size (5.0 vs 5.1 cm, P = .734), median AF duration (23 vs 20 months, P = .513), and long-standing persistent AF (44% vs 33%, P = .280). The primary outcome occurred in 52% of the no-amiodarone group (23 of 44) and 19% of the amiodarone group (8 of 43; P = .001). Cumulative freedom from primary outcome was greater in the amiodarone group (81.4% vs 47.7%, P Amiodarone was discontinued in 18 patients randomized to amiodarone for side effects, bradycardia, or noncompliance. Prophylactic amiodarone reduced early atrial arrhythmia recurrence. These results are consistent with catheter AF ablation findings and should inform recommendations for prophylactic class I/III AAD after surgical AF ablation, regardless of discharge rhythm status. As previously recommended, monitoring for side effects and amiodarone discontinuation by 3 months, for patients in sinus rhythm, is warranted. NCT01416935. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  2. Persistent wandering atrial pacemaker after epinephrine overdosing – a case report

    Directory of Open Access Journals (Sweden)

    Aburawi Elhadi H

    2013-01-01

    Full Text Available Abstract Background Long-term complications of sympathomimetic drug overdosing have not been adequately investigated in infants and young children. Despite reports discouraging their use in children, these formulations are frequently administered for “cold-like symptoms”. Their frequent adverse events are different forms of arrhythmias, including multifocal atrial tachycardia. Case presentation A 3-year-old toddler developed multifocal atrial tachycardia following an iatrogenic overdose of epinephrine accidentally administered intravenously. His ECG showed wandering atrial pacemaker (p-waves with different origins and configurations that persisted for at least one year. This event demonstrated the sensitivity of young children to the sympathomimetic drugs, especially overdosing. Conclusions Health care providers and parents should be warned of toxicities associated with sympathomimetic drug overdosing. Future studies are needed to determine whether wandering atrial pacemaker is a potential long-term complication of high-dose sympathomimetics.

  3. Patient characteristics associated with false arrhythmia alarms in intensive care

    Directory of Open Access Journals (Sweden)

    Harris PR

    2017-04-01

    ventricular bradycardia as true or false. Total monitoring time for each patient was measured, and the number of false alarms per hour was calculated for these six alarm types. Medical records were examined to acquire data on patient characteristics. Results: A total of 461 unique patients (mean age =60±17 years were enrolled, generating a total of 2,558,760 alarms, including all levels of arrhythmia, parameter, and technical alarms. There were 48,404 hours of patient monitoring time, and an average overall alarm rate of 52 alarms/hour. Investigators annotated 12,671 arrhythmia alarms; 11,345 (89.5% were determined to be false. Two hundred and fifty patients (54% generated at least one of the six annotated alarm types. Two patients generated 6,940 arrhythmia alarms (55%. The number of false alarms per monitored hour for patients’ annotated arrhythmia alarms ranged from 0.0 to 7.7, and the duration of these false alarms per hour ranged from 0.0 to 158.8 seconds. Patient characteristics were compared in relation to 1 the number and 2 the duration of false arrhythmia alarms per 24-hour period, using nonparametric statistics to minimize the influence of outliers. Among the significant associations were the following: age ≥60 years (P=0.013; P=0.034, confused mental status (P<0.001 for both comparisons, cardiovascular diagnoses (P<0.001 for both comparisons, electrocardiographic (ECG features, such as wide ECG waveforms that correspond to ventricular depolarization known as QRS complex due to bundle branch block (BBB (P=0.003; P=0.004 or ventricular paced rhythm (P=0.002 for both comparisons, respiratory diagnoses (P=0.004 for both comparisons, and support with mechanical ventilation, including those with primary diagnoses other than respiratory ones (P<0.001 for both comparisons. Conclusion: Patients likely to trigger a higher number of false arrhythmia alarms may be those with older age, confusion, cardiovascular diagnoses, and ECG features that indicate BBB or

  4. [Atrial fibrillation and stroke].

    Science.gov (United States)

    Aamodt, Anne Hege; Sandset, Per Morten; Atar, Dan; Tveit, Arnljot; Russell, David

    2013-08-06

    More than 70,000 Norwegians have atrial fibrillation, which is a major risk factor for ischemic stroke. A large proportion of ischemic strokes caused by atrial fibrillation could be prevented if patients receive optimal prophylactic treatment. This article describes the risk for ischemic stroke in patients with atrial fibrillation, and discusses who should receive prophylactic treatment and which therapy provides the best prevention. The article is based on recently published European, American and Canadian guidelines, a search in PubMed and the authors' own clinical experience. The new risk score CHA2DS2-VASc is better than the CHADS2 score for identifying patients with atrial fibrillation who have a truly low risk of ischemic stroke and are not in need of antithrombotic treatment. Oral anticoagulation therapy is recommended for patients with two or more risk factors for thromboembolism in addition to atrial fibrillation (CHA2DS2-VASc ≥ 2). Patients with atrial fibrillation and a single additional risk factor (CHA2DS2-VASc =1) an individual assessment should be made as to who should receive oral anticoagulants, and for patients with CHA2DS2-VASc = 0 antithrombotic treatment is not recommended. New oral anticoagulants are at least as effective as warfarin for preventing ischemic stroke in patients with nonvalvular atrial fibrillation, they carry a lower risk of cerebral haemorrhage, especially intracranial haemorrhage and are more practical in use. Platelet inhibitors have a minimal role in stroke prevention in patients with atrial fibrillation. Risks stratifying patients using the CHA2DS2-VASc score is a better method for assessing which patients with atrial fibrillation who should receive oral anticoagulation. The introduction of new oral anticoagulants will simplify preventive treatment and hopefully lead to a more efficient anticoagulation treatment in a larger number of patients with atrial fibrillation.

  5. Severe hypoglycemia-induced lethal cardiac arrhythmias are mediated by sympathoadrenal activation.

    Science.gov (United States)

    Reno, Candace M; Daphna-Iken, Dorit; Chen, Y Stefanie; VanderWeele, Jennifer; Jethi, Krishan; Fisher, Simon J

    2013-10-01

    For people with insulin-treated diabetes, severe hypoglycemia can be lethal, though potential mechanisms involved are poorly understood. To investigate how severe hypoglycemia can be fatal, hyperinsulinemic, severe hypoglycemic (10-15 mg/dL) clamps were performed in Sprague-Dawley rats with simultaneous electrocardiogram monitoring. With goals of reducing hypoglycemia-induced mortality, the hypotheses tested were that: 1) antecedent glycemic control impacts mortality associated with severe hypoglycemia; 2) with limitation of hypokalemia, potassium supplementation could limit hypoglycemia-associated deaths; 3) with prevention of central neuroglycopenia, brain glucose infusion could prevent hypoglycemia-associated arrhythmias and deaths; and 4) with limitation of sympathoadrenal activation, adrenergic blockers could prevent hypoglycemia-induced arrhythmic deaths. Severe hypoglycemia-induced mortality was noted to be worsened by diabetes, but recurrent antecedent hypoglycemia markedly improved the ability to survive an episode of severe hypoglycemia. Potassium supplementation tended to reduce mortality. Severe hypoglycemia caused numerous cardiac arrhythmias including premature ventricular contractions, tachycardia, and high-degree heart block. Intracerebroventricular glucose infusion reduced severe hypoglycemia-induced arrhythmias and overall mortality. β-Adrenergic blockade markedly reduced cardiac arrhythmias and completely abrogated deaths due to severe hypoglycemia. Under conditions studied, sudden deaths caused by insulin-induced severe hypoglycemia were mediated by lethal cardiac arrhythmias triggered by brain neuroglycopenia and the marked sympathoadrenal response.

  6. Severe Hypoglycemia–Induced Lethal Cardiac Arrhythmias Are Mediated by Sympathoadrenal Activation

    Science.gov (United States)

    Reno, Candace M.; Daphna-Iken, Dorit; Chen, Y. Stefanie; VanderWeele, Jennifer; Jethi, Krishan; Fisher, Simon J.

    2013-01-01

    For people with insulin-treated diabetes, severe hypoglycemia can be lethal, though potential mechanisms involved are poorly understood. To investigate how severe hypoglycemia can be fatal, hyperinsulinemic, severe hypoglycemic (10–15 mg/dL) clamps were performed in Sprague-Dawley rats with simultaneous electrocardiogram monitoring. With goals of reducing hypoglycemia-induced mortality, the hypotheses tested were that: 1) antecedent glycemic control impacts mortality associated with severe hypoglycemia; 2) with limitation of hypokalemia, potassium supplementation could limit hypoglycemia-associated deaths; 3) with prevention of central neuroglycopenia, brain glucose infusion could prevent hypoglycemia-associated arrhythmias and deaths; and 4) with limitation of sympathoadrenal activation, adrenergic blockers could prevent hypoglycemia-induced arrhythmic deaths. Severe hypoglycemia–induced mortality was noted to be worsened by diabetes, but recurrent antecedent hypoglycemia markedly improved the ability to survive an episode of severe hypoglycemia. Potassium supplementation tended to reduce mortality. Severe hypoglycemia caused numerous cardiac arrhythmias including premature ventricular contractions, tachycardia, and high-degree heart block. Intracerebroventricular glucose infusion reduced severe hypoglycemia–induced arrhythmias and overall mortality. β-Adrenergic blockade markedly reduced cardiac arrhythmias and completely abrogated deaths due to severe hypoglycemia. Under conditions studied, sudden deaths caused by insulin-induced severe hypoglycemia were mediated by lethal cardiac arrhythmias triggered by brain neuroglycopenia and the marked sympathoadrenal response. PMID:23835337

  7. Protective effects of Hawthorn (Crataegus oxyacantha) extract against digoxin-induced arrhythmias in rats.

    Science.gov (United States)

    Alp, Hayrullah; Soner, Burak Cem; Baysal, Tamer; Şahin, Ayşe Saide

    2015-01-01

    Digitalis preparations are commonly used by children and adults with heart diseases worldwide, although excessive doses may cause cardiac effects. The aim of the study is to evaluate the antiarrhythmic effect of Crataegus oxyacantha extract on digoxin-induced arrhythmias in anesthetized Wistar rats. Control and experimental groups were evaluated for arrhythmias induced by digoxin. Fifteen rats (7 as controls and 8 as the experimental group) were included in the study. The dry fruits of 100 mg Crataegus oxyacantha were extracted by percolation method. Digoxin, at a dose of 40 µg/kg/min, was infused to form the arrhythmias in all rats. Simultaneously, the extract was infused into the experimental group, while 0.9% NaCl was infused into control group. Electrocardiographic QRS prolongation and arterial blood pressure changes were analyzed. The experimental group lived longer (62.13±2.20 min) than the controls (p=0.002). On the other hand, the time to beginning of QRS prolongation did not differ between the two groups (p=0.812). Bradycardia was significant in the control group (288.01±10.54 beat/min and p=0.01). The maximum QRS duration was observed in the control group during the digoxin and 0.9% NaCl infusion period (53.29±3.99 ms and p=0.001). Also, the durations of atrial and ventricular arrhythmias were shorter in the experimental group. However, arterial blood pressure dipping was significant in the experimental group (23.67±10.89 mm Hg and p<0.001). Crataegus oxyacantha alcoholic extract produced an antiarrhythmic effect that was induced by digoxin in Wistar rats. However, in the clinical use of this extract, the hypotensive effect should be considered. Also, the alcoholic extract of Crataegus oxyacantha may be an alternative treatment medication for arrhythmias induced by digoxin toxicity in humans.

  8. Targeting sodium channels in cardiac arrhythmia

    NARCIS (Netherlands)

    Remme, Carol Ann; Wilde, Arthur A. M.

    2014-01-01

    Cardiac voltage-gated sodium channels are responsible for proper electrical conduction in the heart. During acquired pathological conditions and inherited sodium channelopathies, altered sodium channel function causes conduction disturbances and ventricular arrhythmias. Although the clinical,

  9. Arrhythmia and exercise intolerance in Fontan patients

    DEFF Research Database (Denmark)

    Idorn, L; Juul, K; Jensen, A S

    2013-01-01

    BACKGROUND: Long-term survival after the Fontan procedure shows excellent results but is associated with a persistent risk of arrhythmias and exercise intolerance. We aimed to analyze the current burden of clinically relevant arrhythmia and severe exercise intolerance in Danish Fontan patients...... and estimated to 99.1% per year. Prevalence of clinically relevant arrhythmia and severe exercise intolerance increased significantly with age and was found in 32% and 85% of patients ≥20years, respectively. Thus, from survival data and logistic regression models the future prevalence of patients, clinically...... relevant arrhythmia and severe exercise intolerance were estimated, revealing a considerable augmentation. Furthermore, resting and maximum cardiac index, resting stroke volume index and pulmonary diffusing capacity decreased significantly with age while diastolic and systolic ventricular function...

  10. Emergency diagnosis and management of pediatric arrhythmias

    Directory of Open Access Journals (Sweden)

    Hanash Carla

    2010-01-01

    Full Text Available True emergencies due to unstable arrhythmias in children are rare, as most rhythm disturbances in this age group are well-tolerated. However, presentation to an emergency department with symptoms of palpitations, fatigue and/or syncope is much more common. Sinus tachycardia is by far the most commonly reported arrhythmia, followed by supraventricular tachycardia. Emergency physicians should be prepared for diagnosis and to acutely manage various types of arrhythmias seen in children, to assess the need for further diagnostic testing, and to determine whether cardiology evaluation and follow-up are needed. This article is intended to provide diagnostic and management guidelines of the most common types of arrhythmias seen in children with structurally normal hearts as well as those associated with congenital heart disease and cardiomyopathies.

  11. β1-Adrenoceptor blocker aggravated ventricular arrhythmia.

    Science.gov (United States)

    Wang, Yan; Patel, Dimpi; Wang, Dao Wu; Yan, Jiang Tao; Hsia, Henry H; Liu, Hao; Zhao, Chun Xia; Zuo, Hou Juan; Wang, Dao Wen

    2013-11-01

    To assess the impact of β1 -adrenoceptor blockers (β1 -blocker) and isoprenaline on the incidence of idiopathic repetitive ventricular arrhythmia that apparently decreases with preprocedural anxiety. From January 2010 to July 2012, six patients were identified who had idiopathic ventricular arrhythmias that apparently decreased (by greater than 90%) with preprocedural anxiety. The number of ectopic ventricular beats per hour (VPH) was calculated from Holter or telemetry monitoring to assess the ectopic burden. The mean VPH of 24 hours from Holter before admission (VPH-m) was used as baseline (100%) for normalization. β1 -Blockers, isoprenaline, and/or aminophylline were administrated successively on the ward and catheter lab to evaluate their effects on the ventricular arrhythmias. Among 97 consecutive patients with idiopathic ventricular arrhythmias, six had reduction in normalized VPHs in the hour before the scheduled procedure time from (104.6 ± 4.6%) to (2.8 ± 1.6%) possibly due to preprocedural anxiety (P < 0.05), then increased to (97.9 ± 9.7%) during β1 -blocker administration (P < 0.05), then quickly reduced to (1.6 ± 1.0%) during subsequent isoprenaline infusion. Repeated β1 -blocker quickly counteracted the inhibitory effect of isoprenaline, and VPHs increased to (120.9 ± 2.4%) from (1.6 ± 1.0%; P < 0.05). Isoprenaline and β1 -blocker showed similar effects on the arrhythmias in catheter lab. In some patients with structurally normal heart and ventricular arrhythmias there is a marked reduction of arrhythmias associated with preprocedural anxiety. These patients exhibit a reproducible sequence of β1 -blocker aggravation and catecholamine inhibition of ventricular arrhythmias, including both repetitive ventricular premature beats and monomorphic ventricular tachycardia. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.

  12. The role of common genetic variants in atrial fibrillation

    DEFF Research Database (Denmark)

    Paludan-Muller, Christian; Svendsen, Jesper H.; Olesen, Morten S.

    2016-01-01

    This review focuses on the genetic basis of atrial fibrillation (AF) and the role of variants in the susceptibility of developing the disease. AF is the most common cardiac arrhythmia affecting 1-2% of the general population. Studies in the last decade have demonstrated that AF, and in particular....... The pathophysiological mechanisms responsible for AF are still far from completely understood, and it is assumed that this arrhythmia represents a complex interplay of genetic predispositions, arrhythmogenic contributors such as electrolytes and inflammatory stimuli as well as contributions from concomitant cardiac...... lone AF, has a substantial genetic component. A number of genome-wide association studies (GWAS) have indicated that common genetic variants, more precisely the so called single-nucleotide polymorphisms (SNPs) are associated with AF. Presently more than 10 genomic regions have been identified using...

  13. Trends in quantitative methods used for atrial fibrillation and ventricular tachycardia analyses

    Directory of Open Access Journals (Sweden)

    Edward J. Ciaccio

    Full Text Available Background: Improved quantitative and computational research efforts would be useful for better and more accurate analysis of heart arrhythmias, and to target catheter ablation sites. To pinpoint useful and leading-edge quantitative methods, research trends of articles published in peer-reviewed journals were identified. Methods: The MEDLINE search tool and an in-house developed software program were used to detect quantitative trends in arrhythmia research. The main keywords used were ‘atrial fibrillation’ and ‘ventricular tachycardia’, which were searched in combination with commonly associated quantitative keywords for signal and imaging data. The search period used was 1960–2013. The linear regression trend over the search period was calculated, and the slope and regression coefficient was tabulated along with the onset year of the trend. Results: In 1960, ‘atrial fibrillation’ and ‘ventricular tachycardia’ appeared in the title or abstract of less than 20 peer-reviewed articles each. A sharp increase in ventricular tachycardia publications occurred from 1975 to 1992 to a peak of over 600 publications; since 1992 the number of ventricular tachycardia studies has leveled. However, the number of atrial fibrillation papers has increased sharply since 1978, surpassing ventricular tachycardia studies in 1993, to over 3500 studies in 2013. From 1960 to 2013, the fraction of ventricular tachycardia papers associated with any particular quantitative keyword, versus the total number of ventricular tachycardia publications, was often greater than the fraction of atrial fibrillation papers associated with the same quantitative keyword, versus the total number of atrial fibrillation publications. Studies published in the bioengineering and bioinformatics literature comprise approximately 10% of all quantitative biomedical studies published on atrial fibrillation and ventricular tachycardia. Conclusions: The

  14. [New method for the treatment of atrial fibrillation: circumferential cryoballoon ablation of the pulmonary vein].

    Science.gov (United States)

    Földesi, Csaba; Kardos, Attila; Mihálcz, Attila; Som, Zoltán; Hódi, Gabriella; Andréka, Péter; Szili-Török, Tamás

    2008-09-21

    Atrial fibrillation is the most frequent arrhythmia with increasing prevalence. Given a limited success rate of drug therapy for atrial fibrillation, interventional treatment options have been developed during the last years. Catheter ablation of atrial fibrillation (until recently the mostly used energy source was radiofrequency energy) has been established as an important therapeutic alternative. Depending on interpersonal (both on patient and operator side) and technical variabilities using radiofrequency energy potentially life-threatening complications such as pulmonary vein stenosis or atrio-esophageal fistulas may occur. Cryoenergy is a novel energy source for transcatheter ablation eliminating the arrhythmia substrate by freezing. The cornerstone of catheter ablation for atrial fibrillation is electrical isolation of the pulmonary veins. During cryoballoon ablation the targeted pulmonary vein transiently occluded by the inflated balloon catheter and using this method a circumferential lesion is created. The success rate of cryoballoon ablation is comparable with the radiofrequency ablation with increased safety. We performed the first cryoballoon ablations for patients with paroxysmal atrial fibrillation in Hungary. On this occasion we review the potential advantages of this technique which may serve as basis for its widespread use in the future.

  15. Blocked Atrial Bi/Trigeminy In Utero Evolving in Supraventricular Tachycardia after Birth

    Directory of Open Access Journals (Sweden)

    V. Martucci

    2012-01-01

    Full Text Available Transient episodes of fetal bradycardia (heart rate less than 110 bpm are usually benign and typically result from increased vagal stimulation in the fetus. Causes of sustained fetal bradycardia include sinus bradycardia, blocked atrial bigeminy/trigeminy, high-degree atrioventricular block, and long QT syndrome. We present the case of a 34-year-old Caucasian patient referred to our department for “blocked atrial bigeminy with pseudobradycardia” detected elsewhere at 33 weeks of gestation. A fetal echocardiography showed during all the examination a blocked atrial trigeminy with a mean fetal heart rate of 100 bpm. After birth three subsequent ECGs until day 3 showed no evidence of atrial extrasystoles, confirming the well-known frequent regression of this kind of fetal benign arrhythmia, but on day 11 recurrence of supraventricular trigeminy and development of episodes of paroxystic supraventricular tachycardia were observed. On the basis of this observation, we recommend that fetuses with complex atrial ectopic beats should be closely monitored before and after birth for evidence of new arrhythmias.

  16. Electrocardiografía clínica: Taquiarritmias supraventriculares de origen atrial

    Directory of Open Access Journals (Sweden)

    Abraham Katime Zúñiga

    2013-10-01

    Full Text Available  Resumen Las arritmias se pueden definir como “cualquier anormalidad en la frecuencia, regularidad o sitio de origen del impulso cardiaco o trastorno de la conducción que produce una alteración de la activación auricular o ventricular”; mientras que taquicardia se define como “frecuencia cardiaca en adultos, mayor de 100 latidos por minuto (lat/ min.”. Por tanto, las taquiarritmias supraventriculares son “aquellas taquicardias que requieren tejido atrial o de conducción atrioventricular para su iniciación y mantenimiento”. En este artículo se expondrán las características electrocardiográficas de aquellas provenientes del tejido auricular. (DUAZARY 2010, 117 - 124AbstractThe arrhythmias are defined as “any abnormality in the frequency, regularity, or site of origin of the cardiac impulse or conduction disorder that produces an alteration in the atrial or ventricular activation”; whereas tachycardia is defined as a “heart rate in adults greater than 100 beats per minute”. Therefore, supraventricular tachyarrhythmias are “those tachycardias who require atrial tissue or atrioventricular conduction for its initiation and maintenance”. This article explains the electrocardiographic characteristics of those arrhythmias from atrial tissue.Keywords: Tachyarrhythmia; Tachycardia; Atrial; Auricular; Fibrilation; Flutter; Sinusal; Electrocardiography.

  17. Effects of beta-blockade on atrial and atrioventricular nodal refractoriness, and atrial fibrillatory rate during atrial fibrillation in pigs

    NARCIS (Netherlands)

    van den Berg, MP; van de Ven, LLM; Witting, W; Crijns, JGM; Haaksma, J; Bel, KJ; de Langen, CDJ; Lie, KI

    1997-01-01

    Despite their widespread use in atrial fibrillation, the effects of beta-adrenoceptor blockers on atrial and atrioventricular (AV) nodal refractoriness, and atrial fibrillatory rate during atrial fibrillation have been incompletely characterised. In particular, it is unknown whether additional

  18. [Giant congenital intrapericardial left atrial appendage aneurysm: about a case and review of the literature].

    Science.gov (United States)

    Zhari, Bouchra; Bellamlih, Habib; Boumdine, Hassan; Amil, Touriya; Bamous, Mehdi; En-Nouali, Hassan

    2016-01-01

    Left atrial appendage aneurysm is a very rare heart anomaly. It may be congenital or acquired, secondary to inflammatory or degenerative processes. Most cases are asymptomatic. The prevalence of these lesions in pediatric age has been very rarely reported. As it can cause potentially fatal arrhythmias or thrombus, surgery is required immediately after diagnosis. This study reports the case of a 14-year-old boy with rapidly progressive dyspnea, palpitations, sensation of repetitive dizziness and fainting, in whom congenital left atrial appendage aneurysm was detected. Diagnosis was based on coronary CTA data. The patient was successfully treated with surgical resection of the aneurysm.

  19. Reduced occurrence of atrial fibrillation in acute myocardial infarction treated with streptokinase

    DEFF Research Database (Denmark)

    Nielsen, F E; Sørensen, H T; Christensen, J H

    1991-01-01

    In a historical follow-up study of 152 hospital patients with acute myocardial infarction, the frequency of life-threatening arrhythmias (ventricular fibrillation, sustained ventricular tachycardia, 3rd degree AV-block, 2nd degree AV-block (Mobitz type II), and asystole) and atrial fibrillation...... in 76 patients treated with streptokinase was compared with their frequency in 76 patients who did not receive a thrombolytic therapy. Among those treated with streptokinase two patients (3%) developed atrial fibrillation, compared with 12 (16%) in the control group (P = 0.009). Life...

  20. Heart rate turbulence and variability in patients with ventricular arrhythmias

    Directory of Open Access Journals (Sweden)

    Diego Tarricone

    2009-08-01

    Full Text Available Background: To evaluate the changes in autonomic neural control mechanisms before malignant ventricular arrhythmias, we measured heart rate variability (HRV and heart rate turbulence (HRT in patients with ventricular tachycardia or fibrillation (Group I; n=6, non sustained ventricular tachycardia (Group II; n=32, frequent premature ventricular beats (Group III; n=26 and with ICD implantation (Group IV; n=11. Methods: Time domain parameters of HRV and turbulence onset (TO and slope (TS were calculated on 24 hour Holter recordings. Normal values were: SDNN > 70 msec for HRV, TO <0% and TS >2.5 msec/RR-I for HRT. Results: Whereas SDNN was within normal range and similar in all study groups, HRT parameters were significantly different in patients who experienced VT/VF during Holter recording. Abnormal TO and/or TS were present in 100% of Group I patients and only in about 50% of Group II and IV. On the contrary, normal HRT parameters were present in 40-70% of Group II, III and IV patients and none of Group I. Conclusions: These data suggest that HRT analysis is more suitable than HRV to detect those transient alterations in autonomic control mechanisms that are likely to play a major trigger role in the genesis of malignant cardiac arrhythmias. (Heart International 2007; 3: 51-7

  1. miRNAs as biomarkers of atrial fibrillation.

    Science.gov (United States)

    Gomes da Silva, Ananília Medeiros; Silbiger, Vivian Nogueira

    2014-12-01

    Atrial fibrillation (AF) is a highly prevalent arrhythmia with pronounced morbidity and mortality. Genetics analysis has established electrophysiological substrates, which determine individual vulnerability to AF occurrence and maintenance. MicroRNAs (miRNAs) found in virtually all organisms function as negative regulators of protein-coding genes. Several studies have suggested a role for miRNAs in the regulation of cardiac excitability and arrhythmogenesis. This review is based on 18 studies conducted between 2009 and 2013 to investigate the association of miRNAs with AF. miRNAs are discussed here as candidate biomarkers for AF in blood and cardiac tissues and as potential targets for AF therapy.

  2. Dynamical mechanism of atrial fibrillation: A topological approach

    Science.gov (United States)

    Marcotte, Christopher D.; Grigoriev, Roman O.

    2017-09-01

    While spiral wave breakup has been implicated in the emergence of atrial fibrillation, its role in maintaining this complex type of cardiac arrhythmia is less clear. We used the Karma model of cardiac excitation to investigate the dynamical mechanisms that sustain atrial fibrillation once it has been established. The results of our numerical study show that spatiotemporally chaotic dynamics in this regime can be described as a dynamical equilibrium between topologically distinct types of transitions that increase or decrease the number of wavelets, in general agreement with the multiple wavelets' hypothesis. Surprisingly, we found that the process of continuous excitation waves breaking up into discontinuous pieces plays no role whatsoever in maintaining spatiotemporal complexity. Instead, this complexity is maintained as a dynamical balance between wave coalescence—a unique, previously unidentified, topological process that increases the number of wavelets—and wave collapse—a different topological process that decreases their number.

  3. [Novel anticoagulants for stroke prevention in atrial fibrillation].

    Science.gov (United States)

    Baumhäkel, M; Schirmer, S H; Böhm, M

    2010-11-01

    The most frequent cardiac arrhythmia and main cause for cardio-embolic stroke is atrial fibrillation. Prophylaxis for thrombembolic events is performed regarding individual risk of patients with either ASS or vitamin-K-antagonists. Efficacy and safety of oral anticoagulation is limited by a narrow therapeutical range as well as by inter- and intraindividual variability of INR-values due to genetic disposition, differences in alimentation, dosage errors, rare control of INR-levels and drug-interactions. New oral anticoagulants with different mechanisms of action may be a promising therapeutic option in future. This review addresses the new anticoagulants Apixaban, Rivaroxban and Dabigatranetexilat with the design and as available the results of the corresponding phase-III-trials in atrial fibrillation (ARISTOTLE, ROCKET-AF, RE-LY). © Georg Thieme Verlag KG Stuttgart · New York.

  4. 'What else can I do?': Insights from atrial fibrillation patient communication online.

    Science.gov (United States)

    Redman, Kirsten; Thorne, Sally; Lauck, Sandra B; Taverner, Tarnia

    2017-03-01

    Many patients with atrial fibrillation experience uncertainty and psychological distress. Internet support groups for atrial fibrillation have yet to be studied. To determine the content and dialogue on an online message board for atrial fibrillation with the purpose of elucidating information and support needs from patient perspectives. Interpretative description methodology was undertaken to explore conversation from a publicly available website for atrial fibrillation over a 3-month period. Individuals interacted with the message board to make sense of their atrial fibrillation events by sharing experiences with medications, complementary and alternative medicine, trigger avoidance and ablation. The opinions of lay experts on the message board, anecdotal stories and hyperlinked Internet data were all highly valued sources of information in the messages. Using the learning gained from the board, individuals proceeded with strategies to treat their atrial fibrillation, often in a trial and error fashion. Throughout the process, individuals came back to the board, to update on their progress and gain assistance from others. The studied atrial fibrillation population had unmet needs for education regarding non-pharmacological approaches to treat atrial fibrillation. In the absence of opportunity to discuss these needs with healthcare professionals, patients may be vulnerable to unproved approaches advocated by Internet peers. Further research is suggested to examine the prevalence of complementary and alternative medicine use in the atrial fibrillation population and to understand better how social media can be utilised to support atrial fibrillation patients.

  5. Fever-induced QTc prolongation and ventricular arrhythmias in individuals with type 2 congenital long QT syndrome

    NARCIS (Netherlands)

    Amin, Ahmad S.; Herfst, Lucas J.; Delisle, Brian P.; Klemens, Christine A.; Rook, Martin B.; Bezzina, Connie R.; Underkofler, Heather A. S.; Holzem, Katherine M.; Ruijter, Jan M.; Tan, Hanno L.; January, Craig T.; Wilde, Arthur A. M.

    2008-01-01

    Type 2 congenital long QT syndrome (LQT-2) is linked to mutations in the human ether a-go-go-related gene (HERG) and is characterized by rate-corrected QT interval (QTc) prolongation, ventricular arrhythmias, syncope, and sudden death. Recognized triggers of these cardiac events include emotional

  6. Impact of atrial fibrillation on the accuracy of oscillometric blood pressure monitoring.

    Science.gov (United States)

    Pagonas, Nikolaos; Schmidt, Sven; Eysel, Jörg; Compton, Friederike; Hoffmann, Clemens; Seibert, Felix; Hilpert, Justus; Tschöpe, Carsten; Zidek, Walter; Westhoff, Timm H

    2013-09-01

    The introduction of automated oscillometric blood pressure monitors was the basis for today's widespread use of blood pressure self-measurement. However, in atrial fibrillation, there is a controversial debate on the use of oscillometry because there is a high variability of heart rate and stroke volume. To date, the accuracy of oscillometric blood pressure monitoring in atrial fibrillation has only been investigated using auscultatory sphygmomanometry as reference method, which may be biased by arrhythmia as well. We performed a cross-sectional study in 102 patients (52 sinus rhythm, 50 atrial fibrillation) assessing the accuracy of an automated and validated oscillometric upper arm (M5 Professional, Omron) and wrist device (R5 Professional, Omron) to invasively assessed arterial pressure. Blood pressure values were calculated as the mean of 3 consecutive measurements. Systolic and diastolic blood pressure did not significantly differ in patients with sinus rhythm and atrial fibrillation, independent of the method of measurement (P>0.05 each). The within-subject variability of the oscillometric measurements was higher in patients with atrial fibrillation compared with sinus rhythm (Pblood pressure, however, did not significantly differ in presence or absence of atrial fibrillation in Bland-Altmann analysis (P>0.05 each). In conclusion, atrial fibrillation did not significantly affect the accuracy of oscillometric measurements, if 3 repeated measurements were performed.

  7. Atrial Fibrillation Predictors: Importance of the Electrocardiogram.

    Science.gov (United States)

    German, David M; Kabir, Muammar M; Dewland, Thomas A; Henrikson, Charles A; Tereshchenko, Larisa G

    2016-01-01

    Atrial fibrillation (AF) is the most common arrhythmia in adults and is associated with significant morbidity and mortality. Substantial interest has developed in the primary prevention of AF, and thus the identification of individuals at risk for developing AF. The electrocardiogram (ECG) provides a wealth of information, which is of value in predicting incident AF. The PR interval and P wave indices (including P wave duration, P wave terminal force, P wave axis, and other measures of P wave morphology) are discussed with regard to their ability to predict and characterize AF risk in the general population. The predictive value of the QT interval, ECG criteria for left ventricular hypertrophy, and findings of atrial and ventricular ectopy are also discussed. Efforts are underway to develop models that predict AF incidence in the general population; however, at present, little information from the ECG is included in these models. The ECG provides a great deal of information on AF risk and has the potential to contribute substantially to AF risk estimation, but more research is needed. © 2015 Wiley Periodicals, Inc.

  8. Genetics and Epigenetics of Arrhythmia and Heart Failure

    Directory of Open Access Journals (Sweden)

    Burcu eDuygu

    2013-10-01

    Full Text Available Heart failure (HF is the end stage of several pathological cardiac conditions including myocardial infarction, cardiac hypertrophy and hypertension. Various molecular and cellular mechanisms are involved in the development of HF. At the molecular level, the onset of HF is associated with reprogramming of gene expression, including downregulation of the alpha-myosin heavy chain (α-MHC gene and sarcoplasmic reticulum Ca2+ ATPase genes and reactivation of specific fetal cardiac genes such as atrial natriuretic factor (ANF and brain natriuretic peptide (BNP. These deviations in gene expression result in structural and electrophysiological changes, which eventually progress to HF. Cardiac arrhythmia is caused by altered conduction properties of the heart, which may arise in response to ischemia, inflammation, fibrosis, aging or from genetic factors. Because changes in the gene transcription program may have crucial consequences as deteriorated cardiac function, understanding the molecular mechanisms involved in the process has become a priority in the field. In this context, various studies besides having identified different DNA methylation patterns in HF patients, have also focused on specific disease processes and their underlying mechanisms, also introducing new concepts such as epigenomics. This review highlights specific genetic mutations associated to the onset and progression of HF, also providing an introduction to epigenetic mechanisms such as histone modifications, DNA methylation and RNA-based modification, and highlights the relation between epigenetics, arrhythmogenesis and HF.

  9. Frequency of supraventricular arrhythmias in patients with idiopathic pulmonary arterial hypertension.

    Science.gov (United States)

    Wen, Li; Sun, Ming-Li; An, Pei; Jiang, Xin; Sun, Kai; Zheng, Lu; Liu, Qian-Qian; Wang, Lan; Zhao, Qin-Hua; He, Jing; Jing, Zhi-Cheng

    2014-11-01

    Supraventricular arrhythmias (SVA) may be risk factors of prognosis in patients with pulmonary arterial hypertension. SVA are increasingly reported in patients with pulmonary hypertension, but little is known about their incidence and outcomes for patients with idiopathic pulmonary arterial hypertension (IPAH) in a large cohort. In this 6-year prospective multicenter study, 280 patients with IPAH were enrolled to investigate the incidence of SVA and assess risk factors, clinical manifestation, management, and impact on survival. The cumulative 6-year incidence of SVA was 15.8%. The most common types of SVA were atrial fibrillation (n = 16) and atrial flutter (n = 13), followed by atrial tachycardia (n = 11). Most episodes of SVA were associated with significant clinical deterioration and right-sided cardiac failure. Sinus rhythm was successfully restored in most patients, resulting in clinical recovery. Increased right ventricular diameter, left atrial area, and higher right atrial pressure and pulmonary vascular resistance were associated with increased risk for experiencing SVA. SVA predicted a greater risk for mortality in a stepwise forward Cox analysis (hazard ratio 4.757, 95% confidence interval 2.695 to 8.397, p SVA, mainly permanent SVA, had a lower survival rate than those who did not develop SVA (p = 0.008). In conclusion, SVA often lead to clinical deterioration and may be associated with an increased risk for death in a large cohort of patients with IPAH. Restoration and maintenance of sinus rhythm are important treatment goals in patients with IPAH. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Atrial mass: a myxoma?

    National Research Council Canada - National Science Library

    Chatzis, Andrew C; Kostopanagiotou, Kostas; Kousi, Theofili; Mitropoulos, Fotios

    2016-01-01

    A middle‐aged woman with a history of resected colorectal cancer and receiving chemotherapy presented with a right atrial mass and the provisional diagnosis of myxoma supported by echocardiography, computed...

  11. Atrial Fibrillation and Stroke

    Science.gov (United States)

    ... faulty heart valves, lung disease, and stimulant or alcohol abuse. Some people will have no identifiable cause for their AF. × Definition Atrial fibrillation (AF) describes the rapid, irregular beating ...

  12. Electrophysiological Studies and Radiofrequency Ablations in Children and Adolescents with Arrhythmia

    Science.gov (United States)

    Simão, Mariana Fernandez; Rios, Matheus Nardi; Leiria, Tiago Luiz Luz; Kruse, Marcelo Lapa; Pires, Leonardo Martins; SantAnna, Roberto Tofani; de Lima, Gustavo Glotz

    2015-01-01

    Background Radiofrequency ablation is the standard non-pharmacological treatment for arrhythmias in pediatric patients. However, arrhythmias and their associated causes have particular features in this population. Objective To analyze the epidemiological characteristics and findings of electrophysiological diagnostic studies and radiofrequency ablations in pediatric patients referred to the Electrophysiology Unit at Instituto de Cardiologia do Rio Grande do Sul, in order to characterize the particularities of this population. Methods Cross-sectional study with 330 electrophysiological procedures performed in patients aged less than 20 years between June 1997 and August 2013. Results In total, 330 procedures (9.6% of the overall procedures) were performed in patients aged less than 20 years (14.33 ± 3.25 years, age range 3 months to 19 years), 201 of which were males (60.9%). A total of 108 (32.7%) electrophysiological diagnostic studies were performed and of these, 48.1% showed abnormal findings. Overall, 219 radiofrequency ablations were performed (66.3%) with a success rate of 84.8%. The presence of an accessory pathway was the most prevalent finding, occurring in 158 cases (72.1%), followed by atrioventricular nodal reentrant tachycardia (16.8%), typical atrial flutter (3.1%) and extrasystoles originating from the right ventricular outflow tract (2.7%). Three patients developed complications during ablation (1.4%). Among congenital heart diseases, which occurred in 51 (15.4%) patients, atrial sept defect was the most frequent (27.4%), followed by ventricular sept defect (25.4%) and Ebstein's anomaly (17.6%). Conclusion Electrophysiological study and radiofrequency ablation are effective tools for diagnosis and treatment of arrhythmias in the pediatric population. PMID:25372472

  13. Atrial fibrillation after coronary artery bypass surgery: Possibilities of prevention

    Directory of Open Access Journals (Sweden)

    Obrenović-Kirćanski Biljana

    2012-01-01

    Full Text Available Atrial fibrillation occurs as a frequent complication after cardiac interventions. It can be found in 5% of all surgical patients, and it is far more common in cardiac (10% - 65% of patients than in non-cardiac procedures. In a number of patients it remains asymptomatic, but may be accompanied by very severe symptoms of hypotension, heart failure, syncope, systemic or pulmonary embolism, perioperative myocardial infarction, cerebrovascular insult and increased operative mortality. Patients whose postoperative course is complicated by atrial fibrillation require longer hospitalization. Possible predisposing factors of this arrhythmia are numerous and are associated with surgery, extensive coronary heart disease and revascularization, and preoperative diseases. According to the recommendations of the European Society of Cardiology orally applied beta-blocker, amiodarone and sotalol can be used for prophylaxis of atrial fibrillation. Following the recommendations, treatment of postoperative atrial fibrillation should include beta-blockers, amiodarone, and in patients with heart failure and left ventricular dysfunction, digoxin. Due to the increased risk of stroke, an anticoagulant protection is necessary. Many studies have been conducted with results supporting the prophylactic use of amiodarone and beta-blockers, while the treatment with new agents such as magnesium, statins, omega-3 fatty acids and inhibitors of the renin-angiotensin-aldosterone system is still being investigated.

  14. Surgical Ablation of Atrial Fibrillation Using Energy Sources.

    Science.gov (United States)

    Brick, Alexandre Visconti; Braile, Domingo Marcolino

    2015-01-01

    Surgical ablation, concomitant with other operations, is an option for treatment in patients with chronic atrial fibrillation. The aim of this study is to present a literature review on surgical ablation of atrial fibrillation in patients undergoing cardiac surgery, considering energy sources and return to sinus rhythm. A comprehensive survey was performed in the literature on surgical ablation of atrial fibrillation considering energy sources, sample size, study type, outcome (early and late), and return to sinus rhythm. Analyzing studies with immediate results (n=5), the percentage of return to sinus rhythm ranged from 73% to 96%, while those with long-term results (n=20) (from 12 months on) ranged from 62% to 97.7%. In both of them, there was subsequent clinical improvement of patients who underwent ablation, regardless of the energy source used. Surgical ablation of atrial fibrillation is essential for the treatment of this arrhythmia. With current technology, it may be minimally invasive, making it mandatory to perform a procedure in an attempt to revert to sinus rhythm in patients requiring heart surgery.

  15. PR Interval Associated Genes, Atrial Remodeling and Rhythm Outcome of Catheter Ablation of Atrial Fibrillation—A Gene-Based Analysis of GWAS Data

    Directory of Open Access Journals (Sweden)

    Daniela Husser

    2017-12-01

    Full Text Available Background: PR interval prolongation has recently been shown to associate with advanced left atrial remodeling and atrial fibrillation (AF recurrence after catheter ablation. While different genome-wide association studies (GWAS have implicated 13 loci to associate with the PR interval as an AF endophenotype their subsequent associations with AF remodeling and response to catheter ablation are unknown. Here, we perform a gene-based analysis of GWAS data to test the hypothesis that PR interval candidate genes also associate with left atrial remodeling and arrhythmia recurrence following AF catheter ablation.Methods and Results: Samples from 660 patients with paroxysmal (n = 370 or persistent AF (n = 290 undergoing AF catheter ablation were genotyped for ~1,000,000 SNPs. Gene-based association was investigated using VEGAS (versatile gene-based association study. Among the 13 candidate genes, SLC8A1, MEIS1, ITGA9, SCN5A, and SOX5 associated with the PR interval. Of those, ITGA9 and SOX5 were significantly associated with left atrial low voltage areas and left atrial diameter and subsequently with AF recurrence after radiofrequency catheter ablation.Conclusion: This study suggests contributions of ITGA9 and SOX5 to AF remodeling expressed as PR interval prolongation, low voltage areas and left atrial dilatation and subsequently to response to catheter ablation. Future and larger studies are necessary to replicate and apply these findings with the aim of designing AF pathophysiology-based multi-locus risk scores.

  16. Fontan conversion to total cavopulmonary connection and arrhythmia ablation: clinical and functional results

    Science.gov (United States)

    Agnoletti, G; Borghi, A; Vignati, G; Crupi, G C

    2003-01-01

    Objectives: To assess the early results of conversion from atriopulmonary to total cavopulmonary connection in patients with failing Fontan operation. Design: Early clinical and instrumental evaluation of patients undergoing conversion from atriopulmonary to total cavopulmonary connection from April 1999 to November 2000. Setting: Tertiary referral centre for congenital heart disease. Patients: 11 Fontan patients (mean (SD) age 20.9 (6.7) years) with refractory arrhythmias or ventricular dysfunction. Interventions: Total cavopulmonary connection, intraoperative ablation, and AAIR pacemaker implantation. Main outcome measures: Holter monitoring, transoesophageal atrial stimulation, ergometric test, and myocardial scintigraphy at a mean (SD) follow up of 16.8 (5.6) months. Results: One early postoperative death occurred. During follow up three patients had relapse of atrial tachycardia, controlled by medical treatment, and two were pacemaker dependent. Transoesophageal stimulation did not induce atrial tachycardia in any patient. Ergometric test showed a diminished exercise tolerance in all but one patient. Mean minute ventilation and maximum oxygen consumption were 62% and 40% of their respective predicted values. Myocardial scintigraphy showed reversal of rest or exercise dysfunction in five patients and improved systemic ventricular function in seven. Mean basal ejection fraction increased from 39.4% (95% confidence interval (CI) 32% to 46%) to 46.5% (95% CI 41.7% to 51.2%) and ejection fraction on effort from 42.3% (95% CI 33.9% to 50.7%) to 50.2% (95% CI 44.5% to 55.9%). Conclusions: Our data show that total cavopulmonary connection associated with intraoperative ablation and pacemaker implantation allows for better control of arrhythmias and improves ventricular function in the majority of patients with failing Fontan. PMID:12527676

  17. Obstructive sleep apnea and cardiac arrhythmias

    Science.gov (United States)

    Hersi, Ahmad Salah

    2010-01-01

    Sleep-disordered breathing (SDB), which includes obstructive sleep apnea (OSA) as its most extreme variant, is characterized by intermittent episodes of partial or complete obstruction of the upper airway, leading to cessation of breathing while asleep. Cardiac arrhythmias are common problems in OSA patients, although the true prevalence and clinical relevance of cardiac arrhythmias remains to be determined. The presence and complexity of tachyarrhythmias and bradyarrhythmias may influence morbidity, mortality and quality of life for patients with OSA. Although the exact mechanisms underlying the link between OSA and cardiac arrhythmias are not well established, they could be some of the same proposed mechanisms relating OSA to different cardiovascular diseases, such as repetitive pharyngeal collapse during sleep, which leads to markedly reduced or absent airflow, followed by oxyhemoglobin desaturation, persistent inspiratory efforts against an occluded airway and termination by arousal from sleep. These mechanisms elicit a variety of autonomic, hemodynamic, humoral and neuroendocrine responses that evoke acute and chronic changes in cardiovascular function. However, despite substantial research effort, the goals of determining in advance which patients will respond most favorably to certain treatment options (such as continuous positive airway pressure, tracheostomy or cardioversion) and the developing alternative treatments remain largely elusive. Therefore, this literature review aims to summarize a broad array of the pathophysiological mechanisms underlying the relationship between OSA and cardiac arrhythmias and the extent of this association from an epidemiological perspective, thereby attempting to assess the effects of OSA treatment on the presence of cardiac arrhythmias. PMID:20351955

  18. Atrial epicardial pacing with long stimulus to P wave interval in a patient with arrhythmogenic right ventricular dysplasia complicated by right atrial thrombosis.

    Science.gov (United States)

    Kazmierczak, J; Kornacewicz-Jach, Z; Wojtarowicz, A

    1999-07-01

    Atrial epicardial pacing with a long stimulus to P wave interval in a patient with arrhythmogenic right ventricular dysplasia complicated by right atrial thrombosis is discussed. Arrhythmogenic right ventricular dysplasia (ARVD) is associated with a high incidence of malignant ventricular arrhythmias. Most patients with ARVD need antiarrhythmic drugs, catheter ablation, or an implantable cardioverter defibrillator. We report a patient with ARVD in whom effective treatment with sotalol caused severe, symptomatic sinus bradycardia requiring permanent pacing. Due to leftward displacement of the right ventricle and the presence of two thrombi in the right atrium, an epicardial atrial lead and AAI pacemaker were implanted. A long stimulus to P wave interval caused by severe dilatation of the right atrium was recorded. During a 6 months of follow-up on sotalol treatment there were neither ventricular tachycardia (VT) attacks nor pacing problems.

  19. Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation.

    Science.gov (United States)

    Lafuente-Lafuente, Carmelo; Valembois, Lucie; Bergmann, Jean-François; Belmin, Joël

    2015-03-28

    Atrial fibrillation is the most frequent sustained arrhythmia. Atrial fibrillation frequently recurs after restoration of normal sinus rhythm. Antiarrhythmic drugs have been widely used to prevent recurrence, but the effect of these drugs on mortality and other clinical outcomes is unclear. This is an update of a review previously published in 2008 and 2012. To determine in patients who have recovered sinus rhythm after having atrial fibrillation, the effects of long-term treatment with antiarrhythmic drugs on death, stroke, embolism, drug adverse effects and recurrence of atrial fibrillation. We updated the searches of CENTRAL in The Cochrane Library (2013, Issue 12 of 12), MEDLINE (to January 2014) and EMBASE (to January 2014). The reference lists of retrieved articles, recent reviews and meta-analyses were checked. Two independent authors selected randomised controlled trials comparing any antiarrhythmic drug with a control (no treatment, placebo, drugs for rate control) or with another antiarrhythmic drug in adults who had atrial fibrillation and in whom sinus rhythm was restored. Post-operative atrial fibrillation was excluded. Two authors independently assessed quality and extracted data. Studies were pooled, if appropriate, using Peto odds ratio (OR). All results were calculated at one year of follow-up. In this update three new studies, with 534 patients, were included making a total of 59 included studies comprising 21,305 patients. All included studies were randomised controlled trials. Allocation concealment was adequate in 17 trials, it was unclear in the remaining 42 trials. Risk of bias was assessed in all domains only in the trials included in this update.Compared with controls, class IA drugs quinidine and disopyramide (OR 2.39, 95% confidence interval (95% CI) 1.03 to 5.59, number needed to treat to harm (NNTH) 109, 95% CI 34 to 4985) and sotalol (OR 2.23, 95% CI 1.1 to 4.50, NNTH 169, 95% CI 60 to 2068) were associated with increased all

  20. Electrophysiologic studies in atrial fibrillation. Slow conduction of premature impulses: a possible manifestation of the background for reentry.

    Science.gov (United States)

    Cosio, F G; Palacios, J; Vidal, J M; Cocina, E G; Gómez-Sánchez, M A; Tamargo, L

    1983-01-01

    Extrastimulus-induced intraatrial conduction delays were measured in 12 patients with documented episodes of atrial fibrillation (AF) by recording atrial electrograms at the high right atrium, His bundle region, and coronary sinus. Seventeen patients with and without heart disease, but without atrial arrhythmias served as the control group. During baseline-paced atrial rhythms, a conduction delay zone could be delineated, near the atrial effective refractory period, during which all extrastimuli produced conduction delays. When compared at the same paced cycle lengths (500 to 650 ms), the patients with AF had shorter atrial effective refractory periods (mean +/- standard deviation 206 +/- 24.1 versus 233 +/- 28.2 in control patients, p less than 0.02), wider conduction delay zones (79 +/- 21.7 ms versus 52 +/- 21 in control patients, p less than 0.01), and longer conduction delays both to the His bundle region (64 +/- 18.3 ms versus 35 +/- 21.7 in control patients, p less than 0.005) and the coronary sinus (76 +/- 18.9 ms versus 35 +/- 16.1 in control patients, p less than 0.001). Repetitive atrial responses were recorded in 6 patients with AF and in 9 control subjects. Sinus nodal function abnormalities were detected in 6 of the patients with fibrillation. Patients with AF had a higher tendency than control subjects to develop slow intraatrial conduction, as well as shorter effective refractory periods. Since both features would favor reentry, they may be the electrophysiologic manifestations of the abnormalities making these patients prone to atrial reentrant arrhythmias. Repetitive atrial responses were of no predictive value. Sinus nodal dysfunction was frequently found, but was not essential for the occurrence of AF.

  1. Effect of vitamin C supplementation in the prevention of atrial fibrillation

    Directory of Open Access Journals (Sweden)

    Jalal Moludi

    2016-02-01

    Full Text Available Background: Recently, the role of inflammation and oxidative stress in the pathophysiology of atrial fibrillation (AF after cardiac surgery has been emphasized. Vitamin C as an antioxidant important role in reducing the incidence of postoperative atrial fibrillation. This study aimed to investigate, administration of vitamin C, as a way to reduce the incidence of atrial fibrillation after coronary bypass surgery. Methods: In this double-blind clinical study, 290 patients in Rajaee Heart Center, from March 2013 to December 2014 who underwent coronary artery bypass surgery were randomly divided into intervention and control groups to receive vitamin C and placebo. The intervention group before the surgery in the operating room received 2 grams of vitamin C intravenously then one gram per day for four days prior to surgery. After the operation, the two groups were compared in terms of the following: Atrial and ventricular arrhythmias after surgery, ICU stay and hospital stay and duration of intubation. Results: 113 cases and 177 controls (191 men and 99 women with a mean age of 55.40±14.40 years in both groups (vitamin C and placebo were enrolled. The incidence of postoperative atrial fibrillation was 55% in the placebo group to 35% in the vitamin C group decreased (P= 0.001. Duration of intubation in the intervention group 11.8 and the control group was 14.14 hours (P= 0.004. The amount of drainage was lower in vitamin C group (P= 0.003. Vitamin C had no effect on the rates of hospital and ICU stay (P= 0.075. There was no significant reduction in threatening arrhythmia (VT and VF in this period (P= 0.159. Conclusion: Vitamin C supplements may reduce atrial fibrillation after coronary artery bypass surgery also can improve conditions such as reducing the duration of intubation. With regard to the safety, these supplements can be recommended for the prevention of atrial fibrillation before coronary artery bypass surgery.

  2. Dronedarone: current evidence for its safety and efficacy in the management of atrial fibrillation

    OpenAIRE

    Schweizer, Patrick A.; Rüdiger Becker; Katus, Hugo A.; et al, ...

    2011-01-01

    Patrick A Schweizer, Rüdiger Becker, Hugo A Katus, Dierk ThomasDepartment of Cardiology, Medical University Hospital, Heidelberg, GermanyAbstract: Atrial fibrillation (AF) is the most common sustained arrhythmia. Management of AF includes rate control, rhythm control if necessary, prevention of thromboembolic events, and treatment of the underlying disease. Rate control is usually achieved by pharmacological suppression of calcium currents or by applying β-blockers or digita...

  3. Impact of controlling atrial fibrillation on outcomes relevant to the patient: focus on dronedarone

    OpenAIRE

    Chahal CAA; Ali O; Hunter RJ; RJ, Schilling

    2012-01-01

    C Anwar A Chahal, Omer Ali, Ross J Hunter, Richard J SchillingDepartment of Cardiology Research, St Bartholomew's Hospital, London, United KingdomAbstract: Atrial fibrillation (AF) is a substantial cause of mortality and morbidity in the Western world. It is a massive burden on health care systems, and its prevalence is expected to double over the next 20 years. Trials evaluating antiarrhythmic drugs or catheter ablation have focused on recurrence of arrhythmia, perhaps neglecting out...

  4. Computational fluid dynamics modelling of left valvular heart diseases during atrial fibrillation

    OpenAIRE

    Stefania Scarsoglio; Andrea Saglietto; Fiorenzo Gaita; Luca Ridolfi; Matteo Anselmino

    2016-01-01

    Background: Although atrial fibrillation (AF), a common arrhythmia, frequently presents in patients with underlying valvular disease, its hemodynamic contributions are not fully understood. The present work aimed to computationally study how physical conditions imposed by pathologic valvular anatomy act on AF hemodynamics. Methods: We simulated AF with different severity grades of left-sided valvular diseases and compared the cardiovascular effects that they exert during AF, compared to lone ...

  5. Triggering Klystrons

    Energy Technology Data Exchange (ETDEWEB)

    Stefan, Kelton D.; /Purdue U. /SLAC

    2010-08-25

    To determine if klystrons will perform to the specifications of the LCLS (Linac Coherent Light Source) project, a new digital trigger controller is needed for the Klystron/Microwave Department Test Laboratory. The controller needed to be programmed and Windows based user interface software needed to be written to interface with the device over a USB (Universal Serial Bus). Programming the device consisted of writing logic in VHDL (VHSIC (Very High Speed Integrated Circuits) hardware description language), and the Windows interface software was written in C++. Xilinx ISE (Integrated Software Environment) was used to compile the VHDL code and program the device, and Microsoft Visual Studio 2005 was used to compile the C++ based Windows software. The device was programmed in such a way as to easily allow read/write operations to it using a simple addressing model, and Windows software was developed to interface with the device over a USB connection. A method of setting configuration registers in the trigger device is absolutely necessary to the development of a new triggering system, and the method developed will fulfill this need adequately. More work is needed before the new trigger system is ready for use. The configuration registers in the device need to be fully integrated with the logic that will generate the RF signals, and this system will need to be tested extensively to determine if it meets the requirements for low noise trigger outputs.

  6. Cardiac arrhythmias associated with spinal cord injury

    DEFF Research Database (Denmark)

    Hector, Sven Magnus; Biering-Sørensen, Tor; Krassioukov, Andrei

    2013-01-01

    CONTEXT/OBJECTIVES: To review the current literature to reveal the incidence of cardiac arrhythmias and its relation to spinal cord injury (SCI). METHODS: Data source: MEDLINE database, 304 hits, and 32 articles were found to be relevant. The relevant articles all met the inclusion criteria: (1......) contained original data (2) on cardiac arrhythmias (3) in humans with (4) traumatic SCI. RESULTS: In the acute phase of SCI (1-14 days after injury) more cranial as well as more severe injuries seemed to increase the incidence of bradycardia. Articles not covering the first 14 days after injury, thus...... as during procedures such as penile vibro-stimulation and tracheal suction. These episodes of bradycardia were seen more often in individuals with cervical injuries. Longitudinal studies with continuous electrocardiogram recordings are needed to uncover the true relation between cardiac arrhythmias and SCI....

  7. A new algorithm to diagnose atrial ectopic origin from multi lead ECG systems--insights from 3D virtual human atria and torso.

    Directory of Open Access Journals (Sweden)

    Erick A Perez Alday

    2015-01-01

    Full Text Available Rapid atrial arrhythmias such as atrial fibrillation (AF predispose to ventricular arrhythmias, sudden cardiac death and stroke. Identifying the origin of atrial ectopic activity from the electrocardiogram (ECG can help to diagnose the early onset of AF in a cost-effective manner. The complex and rapid atrial electrical activity during AF makes it difficult to obtain detailed information on atrial activation using the standard 12-lead ECG alone. Compared to conventional 12-lead ECG, more detailed ECG lead configurations may provide further information about spatio-temporal dynamics of the body surface potential (BSP during atrial excitation. We apply a recently developed 3D human atrial model to simulate electrical activity during normal sinus rhythm and ectopic pacing. The atrial model is placed into a newly developed torso model which considers the presence of the lungs, liver and spinal cord. A boundary element method is used to compute the BSP resulting from atrial excitation. Elements of the torso mesh corresponding to the locations of the placement of the electrodes in the standard 12-lead and a more detailed 64-lead ECG configuration were selected. The ectopic focal activity was simulated at various origins across all the different regions of the atria. Simulated BSP maps during normal atrial excitation (i.e. sinoatrial node excitation were compared to those observed experimentally (obtained from the 64-lead ECG system, showing a strong agreement between the evolution in time of the simulated and experimental data in the P-wave morphology of the ECG and dipole evolution. An algorithm to obtain the location of the stimulus from a 64-lead ECG system was developed. The algorithm presented had a success rate of 93%, meaning that it correctly identified the origin of atrial focus in 75/80 simulations, and involved a general approach relevant to any multi-lead ECG system. This represents a significant improvement over previously developed

  8. Clinical signs and left atrial size in cats with cardiovascular disease in general practice.

    Science.gov (United States)

    Smith, S; Dukes-McEwan, J

    2012-01-01

    To evaluate population characteristics, clinical signs and simple echocardiographic measurements of a general practice population of cats, in identifying characteristics that reliably distinguish cats with heart disease from others, including those with respiratory disease, using widely available techniques. Cats presented with heart disease (n=103), respiratory disease (n=19) and a normal group (n=29) were prospectively recruited. All cats were subject to full clinical examination, echocardiography and additional diagnostic procedures as appropriate to establish definitive diagnosis. Cats were classified as Group 1: no heart disease ± respiratory disease; Group 2: heart disease with no clinical signs; Group 3: heart disease with clinical signs. Murmur, gallop sound and arrhythmia prevalence and left atrial size were compared between the groups. Low heart rates prevailed in Group 3. Murmurs were prevalent in Group 2, but in Group 3 prevalence was significantly lower. Dyspnoea, gallop sounds, arrhythmias and left atrial diameter were significantly different between groups. Heart rate is unreliable for diagnosing heart failure in cats. Absence of murmur is prevalent in cats with clinical signs of heart failure, but arrhythmia and gallop sounds are prevalent. Echocardiographic measurement of left atrial diameter >16.5 mm may distinguish heart failure from respiratory disease in general practice. © 2011 British Small Animal Veterinary Association.

  9. Distinct Cellular Basis for Early Cardiac Arrhythmias, the Cardinal Manifestation of Arrhythmogenic Cardiomyopathy, and the Skin Phenotype of Cardiocutaneous Syndromes.

    Science.gov (United States)

    Karmouch, Jennifer; Zhou, Qiong Q; Miyake, Christina Y; Lombardi, Raffaella; Kretzschmar, Kai; Bannier-Hélaouët, Marie; Clevers, Hans; Wehrens, Xander H T; Willerson, James T; Marian, Ali J

    2017-12-08

    Arrhythmogenic cardiomyopathy is caused primarily by mutations in genes encoding desmosome proteins. Ventricular arrhythmias are the cardinal and typically early manifestations, whereas myocardial fibroadiposis is the pathological hallmark. Homozygous DSP (desmoplakin) and JUP (junction protein plakoglobin) mutations are responsible for a subset of patients with arrhythmogenic cardiomyopathy who exhibit cardiac arrhythmias and dysfunction, palmoplanter keratosis, and hair abnormalities (cardiocutaneous syndromes). To determine phenotypic consequences of deletion of Dsp in a subset of cells common to the heart and skin. Expression of CSPG4 (chondroitin sulfate proteoglycan 4) was detected in epidermal keratinocytes and the cardiac conduction system. CSPG4pos cells constituted ≈5.6±3.3% of the nonmyocyte cells in the mouse heart. Inducible postnatal deletion of Dsp under the transcriptional control of the Cspg4 locus led to ventricular arrhythmias, atrial fibrillation, atrioventricular conduction defects, and death by 4 months of age. Cardiac arrhythmias occurred early and in the absence of cardiac dysfunction and excess cardiac fibroadipocytes, as in human arrhythmogenic cardiomyopathy. The mice exhibited palmoplantar keratosis and progressive alopecia, leading to alopecia totalis, associated with accelerated proliferation and impaired terminal differentiation of keratinocytes. The phenotype is similar to human cardiocutaneous syndromes caused by homozygous mutations in DSP. Deletion of Dsp under the transcriptional regulation of the CSPG4 locus led to lethal cardiac arrhythmias in the absence of cardiac dysfunction or fibroadiposis, palmoplantar keratosis, and alopecia, resembling the human cardiocutaneous syndromes. The findings offer a cellular basis for early cardiac arrhythmias in patients with arrhythmogenic cardiomyopathy and cardiocutaneous syndromes. © 2017 American Heart Association, Inc.

  10. Prevalence, prognostic significance, and treatment of atrial fibrillation in congestive heart failure with particular reference to the DIAMOND-CHF study

    DEFF Research Database (Denmark)

    Pedersen, Ole Dyg; Brendorp, Bente; Køber, Lars

    2003-01-01

    Atrial fibrillation is a growing health problem and the most common cardiac arrhythmia, affecting 5% of persons above the age of 65 years. The number of hospital discharges for atrial fibrillation has more than doubled in the past decade. It occurs very often in patients with congestive heart...... fibrillation is a risk factor in congestive heart failure patients. In the last 10-15 years, significant advances in the treatment of heart failure have improved survival, whereas effective management of atrial fibrillation in heart failure patients still awaits similar progress. Empirically, two strategies...

  11. Scintigraphic assessment of cardiac sympathetic innervation with I-123-metaiodobenzylguanidine in cardiomyopathy. Special reference to cardiac arrhythmia

    Energy Technology Data Exchange (ETDEWEB)

    Asano, Takahisa; Otsuka, Nobuaki; Sone, Teruki; Mimura, Hiroaki; Yanagimoto, Shinichi; Tomomitsu, Tatsushi; Fukunaga, Masao [Kawasaki Medical School, Kurashiki, Okayama (Japan); Morita, Koichi

    1999-07-01

    Cardiac sympathetic imagings with I-123-metaiodobenzylguanidine (MIBG) were carried out in 5 cases with dilated cardiomyopathy (DCM), 26 cases with hypertrophic cardiomyopathy (HCM), and 4 cases without cardiac disease as a control to assess cardiac sympathetic innervation qualitatively and quantitatively, and to clarify the relation of MIBG accumulation to arrhythmia. MIBG scintigraphy was performed at 15 min. (early image) and 4 hr. (delayed image) after intravenous injection of MIBG 111 MBq. The MIBG uptake ratio of mediastinum (H/M) and the cardiac washout rate (WR) from early to delayed images were calculated. On both early and delayed SPECTs, MIBG uptake was assessed by defect scores (DSs). Regarding the cases with HCM, the MIBG uptake ratio, WR, and DS were also compared in cases with and without arrhythmia. In DCM, the MIBG uptake on delayed SPECT was markedly low, the H/M ratio was significantly lower, and the DS was significantly higher than in the control (all p<0.05). As for the WR, there was no significant difference between HCM, DCM and the control. In HCM, significantly reduced MIBG uptake was observed in cases with ventricular techycardia (VT) and in cases with atrial fibrillation (Af), as compared with cases without arrhythmia (all p<0.05). There results suggest that MIBG scintigraphy might be a useful tool in the assessment of cardiac sympathetic abnormalities in cardiomyopathy, especially in cases with arrhythmia. (author)

  12. Left atrial appendage occlusion

    Directory of Open Access Journals (Sweden)

    Ahmad Mirdamadi

    2013-01-01

    Full Text Available Left atrial appendage (LAA occlusion is a treatment strategy to prevent blood clot formation in atrial appendage. Although, LAA occlusion usually was done by catheter-based techniques, especially percutaneous trans-luminal mitral commissurotomy (PTMC, it can be done during closed and open mitral valve commissurotomy (CMVC, OMVC and mitral valve replacement (MVR too. Nowadays, PTMC is performed as an optimal management of severe mitral stenosis (MS and many patients currently are treated by PTMC instead of previous surgical methods. One of the most important contraindications of PTMC is presence of clot in LAA. So, each patient who suffers of severe MS is evaluated by Trans-Esophageal Echocardiogram to rule out thrombus in LAA before PTMC. At open heart surgery, replacement of the mitral valve was performed for 49-year-old woman. Also, left atrial appendage occlusion was done during surgery. Immediately after surgery, echocardiography demonstrates an echo imitated the presence of a thrombus in left atrial appendage area, although there was not any evidence of thrombus in pre-pump TEE. We can conclude from this case report that when we suspect of thrombus of left atrial, we should obtain exact history of previous surgery of mitral valve to avoid misdiagnosis clotted LAA, instead of obliterated LAA. Consequently, it can prevent additional evaluations and treatments such as oral anticoagulation and exclusion or postponing surgeries including PTMC.

  13. A Giant Left Atrial Myxoma

    Directory of Open Access Journals (Sweden)

    Medhat F. Zaher

    2014-01-01

    Full Text Available Atrial myxomas are the most common primary cardiac tumors. Patients with left atrial myxomas generally present with mechanical obstruction of blood flow, systemic embolization, and constitutional symptoms. We present a case of an unusually large left atrial myxoma discovered incidentally in a patient with longstanding dyspnea being managed as bronchial asthma.

  14. The role of Interleukin-6, its -174 G>C polymorphism and C-reactive protein in idiopathic cardiac arrhythmias in children.

    Science.gov (United States)

    Szydlowski, L; Skierska, A; Markiewicz-Loskot, G; Mazurek, B; Morka, A; Undas, A

    2013-01-01

    ABSTRACT Purpose: Knowledge about the role of inflammation in the pathogenesis of arrhythmias in children is limited. Several studies have suggested a relationship between plasma IL-6 levels and/or the -174G>C IL-6 gene polymorphism and atrial fibrillation in adults. Our present study was performed to investigate whether serum IL-6, -174G>C IL-6 polymorphism and C-reactive protein (CRP) are associated with arrhythmias of unknown origin in children. The study included 126 children diagnosed with supraventricular or ventricular arrhythmia. Patients with congenital heart defects as well as arrhythmias of known origin were excluded from the study. The control group comprised 37 healthy children. The 24 hour Holter electrocardiography monitoring was performed. Serum IL-6, -174 GC IL-6 polymorphism and CRP concentrations were measured on admission. There were no differences in IL-6, CRP and -174 G>C IL-6 genotype distribution between the control and patient groups. No significant differences in IL-6, CRP and -174 G>C IL-6 genotypes were observed between children with supraventricular or ventricular arrhythmias. The severity of arrhythmias showed also no associations with IL-6, CRP or -174 G>C IL-6 genotypes. The results suggest that idiopathic cardiac arrhythmias of unknown origin in children are not associated with selected pro-inflammatory markers of infections i.e. elevated IL-6, CRP or -174 G>C IL-6 polymorphism. This new information can effectively reduce the total financial cost of unnecessary diagnosis and treatment of children affected by cardiac arrhythmias.

  15. Use of Intravenous Amiodarone in the Treatment of Nifekalant-Resistant Arrhythmia: A Review of 11 Consecutive Cases with Severe Heart Failure

    Directory of Open Access Journals (Sweden)

    Tohru Ujihira

    2011-05-01

    Full Text Available Background: Both nifekalant hydrochloride (NIF, a selective IKr blocker, and intravenous amiodarone (AMD, a multi-channel (including IKr blocking blocker, have been reported to be efficacious for refractory arrhythmias. However, the optimal use of those antiarrhythmic drugs for refractory arrhythmia with severe heart failure has not been established. Intravenous AMD might be effective for arrhythmias refractory to NIF in patients with severe heart failure. Here, we report that intravenous amiodarone was effective in the treatment of nifekalant-resistant in a group of arrhythmia patients with severe heart failure. Methods: Eleven severe heart failure patients who had received intravenous AMD for treatment of NIF-resistant arrhythmias were included in this study, and retrospective analysis was performed. Clinical efficacy (terminative and preventive effects on arrhythmia of intravenous AMD was evaluated. Results: All cases were emergent cases and had depressed left ventricular ejection fraction (30 ± 13%. Clinical arrhythmias were ventricular fibrillation (VF in four patients, ventricular tachycardia (VT in six patients, and atrial fibrillation (AF in one patient. NIF was administered to all patients by intravenous injection. After administration of NIF, VT/VF/AF was terminated in seven of the 10 patients, but a preventive effect was not obtained in any of the patients (NIF-resistance. Intravenous AMD (maintenance dose: 484 ± 166 mg/day was effective both in termination (80% and in prevention (80% of VT/VF events in those patients. It was also effective in termination (80% and prevention (60% of AF events refractory to NIF. During continuous AMD administration, no significant adverse effects or proarrhythmic effects were observed in any of the patients. Five patients died within one month, but there was no arrhythmic deaths. Conclusions: Intravenous AMD was effective in NIF-resistant lethal arrhythmias and was relatively safe in emergent cases

  16. Prevalence of and risk factors for perioperative arrhythmias in neonates and children after cardiopulmonary bypass: continuous holter monitoring before and for three days after surgery

    Directory of Open Access Journals (Sweden)

    Vazquez-Jimenez Jaime F

    2010-10-01

    Full Text Available Abstract Background A comprehensive evaluation of postoperative arrhythmias following surgery for congenital heart disease by continuous Holter monitoring has not been carried out. We aimed, firstly, to establish the time course of pre- and early postoperative arrhythmias by beat-to-beat analysis following cardiopulmonary bypass and, secondly, to examine which surgical procedures present risk factors for specific arrhythmias. Methods 494 consecutive patients, including 96 neonates, were studied with serial 24-hour Holter electrocardiograms before as well as uninterruptedly during the first 72 hours after surgery and prior to discharge. Results Within 24 hours of surgery 59% of the neonates and 79% of the older children developed arrhythmias. Junctional ectopic tachycardia occurred in 9% of neonates and 5% of non-neonates and ventricular tachycardia in 3% and 15%, respectively. For neonates, male sex and longer cross-clamping time independently increased the risk for arrhythmias (odds ratios 2.83 and 1.96/minute, respectively. Ventricular septal defect repair was a strong risk factor for junctional ectopic tachycardia in neonates and in older children (odds ratios 18.8 and 3.69, respectively. For infants and children, older age (odds ratio 1.01/month and closure of atrial septal defects (odds ratio 2.68 predisposed to arrhythmias of any type. Conclusions We present the largest cohort of neonates, infants and children that has been prospectively studied for the occurrence of arrhythmias after cardiac surgery. Postoperative arrhythmias are a frequent and transient phenomenon after cardiopulmonary bypass, provoked both by mechanical irritation of the conduction system and by humoral factors.

  17. Ablation for atrial fibrillation: an evidence-based analysis.

    Science.gov (United States)

    2006-01-01

    To review the effectiveness, safety, and costing of ablation methods to manage atrial fibrillation (AF). The ablation methods reviewed were catheter ablation and surgical ablation. Atrial fibrillation is characterized by an irregular, usually rapid, heart rate that limits the ability of the atria to pump blood effectively to the ventricles. Atrial fibrillation can be a primary diagnosis or it may be associated with other diseases, such as high blood pressure, abnormal heart muscle function, chronic lung diseases, and coronary heart disease. The most common symptom of AF is palpitations. Symptoms caused by decreased blood flow include dizziness, fatigue, and shortness of breath. Some patients with AF do not experience any symptoms. According to United States data, the incidence of AF increases with age, with a prevalence of 1 per 200 people aged between 50 and 60 years, and 1 per 10 people aged over 80 years. In 2004, the Institute for Clinical Evaluative Sciences (ICES) estimated that the rate of hospitalization for AF in Canada was 582.7 per 100,000 population. They also reported that of the patients discharged alive, 2.7% were readmitted within 1 year for stroke. One United States prevalence study of AF indicated that the overall prevalence of AF was 0.95%. When the results of this study were extrapolated to the population of Ontario, the prevalence of AF in Ontario is 98,758 for residents aged over 20 years. Currently, the first-line therapy for AF is medical therapy with antiarrhythmic drugs (AADs). There are several AADs available, because there is no one AAD that is effective for all patients. The AADs have critical adverse effects that can aggravate existing arrhythmias. The drug selection process frequently involves trial and error until the patient's symptoms subside. Ablation has been frequently described as a "cure" for AF, compared with drug therapy, which controls AF but does not cure it. Ablation involves directing an energy source at cardiac tissue

  18. A novel KCND3 gain-of-function mutation associated with early-onset of persistent lone atrial fibrillation

    DEFF Research Database (Denmark)

    Olesen, Morten Steen Salling; Refsgaard, Lena; Holst, Anders Gaarsdal

    2013-01-01

    AimsAtrial fibrillation (AF) is the most common cardiac arrhythmia, and early-onset lone AF has been linked to mutations in genes encoding ion channels. Mutations in the pore forming subunit K4.3 leading to an increase in the transient outward potassium current (I) have previously been associated...

  19. Cost-effectiveness of screening for atrial fibrillation in primary care with a handheld, single-lead electrocardiogram device in the Netherlands

    NARCIS (Netherlands)

    Jacobs, Maartje S; Kaasenbrood, Femke; Postma, Maarten J; van Hulst, Marinus; Tieleman, Robert G

    2016-01-01

    AIMS: Atrial fibrillation (AF) is the most common arrhythmia and prevalence increases with age. Patients with AF have a high risk of stroke, and screening for AF is recommended in all people aged 65 years or older to identify patients eligible for stroke prevention. A handheld, single-lead

  20. Cardiac arrhythmias associated with spinal cord injury.

    Science.gov (United States)

    Hector, Sven Magnus; Biering-Sørensen, Tor; Krassioukov, Andrei; Biering-Sørensen, Fin

    2013-11-01

    To review the current literature to reveal the incidence of cardiac arrhythmias and its relation to spinal cord injury (SCI). MEDLINE database, 304 hits, and 32 articles were found to be relevant. The relevant articles all met the inclusion criteria: (1) contained original data (2) on cardiac arrhythmias (3) in humans with (4) traumatic SCI. In the acute phase of SCI (1-14 days after injury) more cranial as well as more severe injuries seemed to increase the incidence of bradycardia. Articles not covering the first 14 days after injury, thus describing the chronic phase of SCI, showed that individuals with SCI did not have a higher incidence of cardiac arrhythmias compared with able-bodied controls. Furthermore, their heart rate did not differ significantly. Penile vibro-stimulation was the procedure investigated most likely to cause bradycardia, which in turn was associated with episodes of autonomic dysreflexia. The incidence of bradycardia was found to be 17-77% for individuals with cervical SCI. For individuals with thoracolumbar SCI, the incidence was 0-13%. Bradycardia was commonly seen in the acute stage after SCI as well as during procedures such as penile vibro-stimulation and tracheal suction. These episodes of bradycardia were seen more often in individuals with cervical injuries. Longitudinal studies with continuous electrocardiogram recordings are needed to uncover the true relation between cardiac arrhythmias and SCI.

  1. Risk of arrhythmia induced by psychotropic medications

    DEFF Research Database (Denmark)

    Fanoe, Søren; Kristensen, Diana; Fink-Jensen, Anders

    2014-01-01

    Several drugs used in the treatment of mental diseases are associated with an increased risk of sudden cardiac death (SCD). A general cause-relationship between the intake of these drugs and SCD is unattainable, but numerous case reports of drug-induced malignant arrhythmia and epidemiological st...

  2. Improved arrhythmia detection in implantable loop recorders

    DEFF Research Database (Denmark)

    Brignole, M.; Black, C.L.B.; Sutton, R.

    2008-01-01

    Improved Arrhythmia Detection. Introduction: Implantable loop recorders (ILR) have an automatic arrhythmia detection feature that can be compromised by inappropriately detected episodes. This study evaluated a new ILR sensing and detection scheme for automatically detecting asystole, bradyarrhyth......Improved Arrhythmia Detection. Introduction: Implantable loop recorders (ILR) have an automatic arrhythmia detection feature that can be compromised by inappropriately detected episodes. This study evaluated a new ILR sensing and detection scheme for automatically detecting asystole......, bradyarrhythmia, and tachyarrhythmia events, which is implemented in the next generation device (Reveal DX/XT). Methods and Results: The new scheme employs an automatically adjusting R-wave sensing threshold, enhanced noise rejection, and algorithms to detect asystole, bradyarrhythmia, and tachyarrhythmia....... Performance of the new algorithms was evaluated using 2,613 previously recorded, automatically detected Reveal Plus episodes from 533 patients. A total of 71.9% of episodes were inappropriately detected by the original ILR, and at least 88.6% of patients had one or more inappropriate episodes, with most...

  3. The heart is a representation of life: an exploration of illness beliefs in couples living with atrial fibrillation.

    Science.gov (United States)

    Dalteg, Tomas; Sandberg, Jonas; Malm, Dan; Sandgren, Anna; Benzein, Eva

    2017-11-01

    To explore illness beliefs in couples where one spouse has atrial fibrillation. Beliefs are the lenses through which we view the world, guiding our behaviour and constructing our lives. Couples evolve an ecology of beliefs from their interaction whereby their actions and choices arise from their beliefs. Atrial fibrillation is a common cardiac arrhythmia that has implications for both patients and partners. A couple's illness beliefs play an important role in convalescence and illness management, and no previous studies have explored illness beliefs in couples living with atrial fibrillation. A qualitative hermeneutic design. Data collection constituted in-depth interviews with nine couples (patient and partner together). Hermeneutic philosophy as described by Gadamer was used to interpret and to understand illness beliefs in couples living with atrial fibrillation. The findings revealed both core illness beliefs and secondary illness beliefs. From the core illness belief 'The heart is a representation of life', two secondary illness beliefs were derived: atrial fibrillation is a threat to life and atrial fibrillation can and must be explained. From the core illness belief 'Change is an integral part of life', two secondary illness beliefs were derived: atrial fibrillation is a disruption in our lives and atrial fibrillation will not interfere with our lives. Finally, from the core illness belief 'Adaptation is fundamental in life', two secondary illness beliefs were derived: atrial fibrillation entails adjustment in daily life and atrial fibrillation entails confidence in and adherence to professional care. Couples' interaction has developed mutual illness beliefs regarding atrial fibrillation that guide them in their daily lives and influence their decisions. The adoption of a family-centred perspective in cardiovascular care settings is warranted. © 2017 John Wiley & Sons Ltd.

  4. Simplified progressive approach for the ablation of scar related atrial macroreentrant tachycardias.

    Science.gov (United States)

    Nava, Santiago; Iturralde-Torres, Pedro; Márquez, Manlio F; Gómez-Flores, Jorge; Cline, Bernardo; Colin-Lizalde, Luis; Victoria, Diana; Hermosillo, Antonio G

    2013-01-01

    Radiofrequency ablation of scar related right atrial flutter is challenging. Long procedures, prolonged fluoroscopic times and high percentages of recurrences are of concern. We present a simple and progressive approach based on a single electroanatomic map of the right atrium. Twenty-two consecutive patients with atrial flutter and history of cardiac surgery were included. An electrophysiologic study was performed to define localization (left or right) and cavo-tricuspid isthmus participation using entrainment mapping. After a critical isthmus was localized, ablation was performed with an external irrigated tip catheter with a power limit of 30 W. Potential ablation sites were confirmed by entrainment. The predominant cardiopathy was atrial septal defect. All arrhythmias were localized in the right atrium; mean cycle length of the clinical flutter was 274 ± 31 ms. Only 40% had cavo-tricuspid isthmus participation. None of the patients with successful ablation had recurrences after 13 ± 9.4 months of follow-up. A progressive approach with only one activation/voltage CARTO(®) map of the atrium and ablation of all potential circuits is a highly effective method for ablating scar related macroreentrant atrial arrhythmias. Copyright © 2012 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

  5. Neonatal atrial flutter after insertion of an intracardiac umbilical venous catheter

    Directory of Open Access Journals (Sweden)

    Marcos Moura de Almeida

    2016-03-01

    Full Text Available Abstract Objective: To describe a case of neonatal atrial flutter after the insertion of an intracardiac umbilical venous catheter, reporting the clinical presentation and reviewing the literature on this subject. Case description: A late-preterm newborn, born at 35 weeks of gestational age to a diabetic mother and large for gestational age, with respiratory distress and rule-out sepsis, required an umbilical venous access. After the insertion of the umbilical venous catheter, the patient presented with tachycardia. Chest radiography showed that the catheter was placed in the position that corresponds to the left atrium, and traction was applied. The patient persisted with tachycardia, and an electrocardiogram showed atrial flutter. As the patient was hemodynamically unstable, electric cardioversion was successfully applied. Comments: The association between atrial arrhythmias and misplaced umbilical catheters has been described in the literature, but in this case, it is noteworthy that the patient was an infant born to a diabetic mother, which consists in another risk factor for heart arrhythmias. Isolated atrial flutter is a rare tachyarrhythmia in the neonatal period and its identification is essential to establish early treatment and prevent systemic complications and even death.

  6. [Echocardiographic factors predictive of restoration and maintenance of sinus rhythm after reduction of atrial fibrillation].

    Science.gov (United States)

    Ben Khalfallah, A; Sanaa, I

    2007-09-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia. While the arrhythmia was initially thought to be little more than a nuisance, it is now clear that AF has a significant negative impact on quality of life and a corresponding increase in both morbidity and mortality. The aim of this study was to identify Doppler echographic patterns that allow prediction of atrial fibrillation reduction and maintenance of sinus rhythm within 12 months. One hundred and thirty patients having permanent atrial fibrillation, recent (51) or chronic (79) are included in the study, excepting those with valvular heart disease or thyroid dysfunction. The mean age was 63.5 +/- 11.3 years. Both transthoracic and transoesophageal echocardiography was performed using a Philips SONOS 5500 Echograph, before cardioversion. Were studied: end diastolic and systolic left ventricular diameters, left ventricular ejectionnal fraction, left atrial area (LAA), left atrial diameter, left atrial appendage area and peak emptying velocities of the left atrial appendage (PeV). Sinus rhythm was re-established in 102 patients (44 having recent and 58 chronic atrial fibrillation). Sinus rhythm was maintained for 12 months in 79 patients. Within the echographic parameters studied, the left atrial area (LAA) and peak emptying velocities of left atrial appendage (PeV) before cardioversion were the best predictors of restoration of sinus rhythm. On monovariate analysis, SOG is significantly lower and PicV is significantly higher in patients whose sinus rhythm had been restored in comparison with those with permanent atrial fibrillation. (Mean SOG: 27.7 +/- 7.62 vs. 34 +/- 7,6 cm2, ppredict on mono and multivariate analysis (p=0.05, OR=0.5, IC=0.36 à 3.56), re-establishing of sinus rhythm whereas in patients with chronic atrial fibrillation, peak emptying velocity of left atrial appendage predict better re-establishing of sinus rhythm (p=0.04, OR=1.29, IC=0.12 à 4.23). The threshold values of LAA and Pe

  7. Surgical Radiofrequency MAZE III Ablation for Treatment of Atrial Fibrillation During Open Heart Surgery

    Directory of Open Access Journals (Sweden)

    Fariborz Akbarzadeh

    2006-05-01

    Full Text Available Background: Atrial fibrillation is a common arrhythmia in patients with rheumatic mitral and other valve diseases who are candidates for valve repair surgeries. Conversion of rhythm to sinus has positive effects on quality of life and lower use of medications. The aim of this clinical study was to evaluate the effectiveness of the radiofrequency ablation Maze III procedure in the treatment of atrial fibrillation associated with rheumatic heart valve disease. Methods: We applied a modified Cox III Maze procedure using radiofrequency ablation in the treatment of atrial fibrillation associated with rheumatic heart valve disease and evaluated the outcome of 20 patients of atrial fibrillation associated rheumatic valve disease who underwent radiofrequency ablation Maze III procedure plus heart valve surgery. Demographic, echocardiographic, Electrocardiographic and Doppler study data were calculated before surgery, six month and one year after surgery.. Results: No perioperative deaths occurred in the study group. Duration of additional time for doing radiofrequency ablation was about 22 minutes. Freedom from atrial fibrillation was 85% and 75% at six months and one year follow-up respectively... Conclusions: The addition of the radiofrequency ablation Maze procedure to heart valve surgery is safe and effective in the treatment of atrial fibrillation associated with rheumatic heart valve disease.

  8. [The cholinergic non-excitability phenomenon in the atrial myocardium of lower vertebrates].

    Science.gov (United States)

    Abramochkin, D V; Kuz'min, V S; Sukhova, G S; Rozenshtraukh, L V

    2009-06-01

    Changes of electric activity induced by acetylcholine were studied in atrial myocardium of fishes (cod and carp) and reptilians (lizard and grass-snake). Standart microelectrode technique and novel method of optical mapping were used in the study. Acetylcholine (1-50 microM) provoked decrease of the action potential amplitude down to full inhibition of electrical activity in wide regions of atrium of cod and carp. We define this phenomenon as cholinergic inexcitability. In other regions excitation persisted even during action of 500 microM acetylcholine. In atria of lizard and grass-snake acetylcholine caused shortening of action potential without changes in it's amplitude. Local cholinergic inexcitability, shown in the atrial myocardium of fishes, is quite similar to the phenomenon, that was described earlier in the atria of frogs. It presents the heart of fish as an interesting model for study of mechanisms of cholinergic atrial arrhythmias initiation.

  9. Anesthetic management of an AAI pacemaker patient with paroxysmal atrial fibrillation during colorectal surgery.

    Science.gov (United States)

    Lin, Jui-An; Borel, Cecil O; Wang, Wen-Been; Wong, Chih-Shung; Yeh, Chun-Chang; Yang, Chih-Ping; Wu, Ching-Tang

    2006-08-01

    Perioperative management of patients with cardiac pacemakers may be challenging because of the increasing sophistication of these devices. We report a case of a patient with paroxysmal atrial fibrillation (PAF) and with a permanent AAIR (bipolar atrial-inhibited adaptive rate) pacemaker who suffered life-threatening episodes of arrhythmias during operation. The first episode was vagally induced PAF during bowel manipulation; the second, induced by the increased pacing threshold from the external electric cardioversion and hyperkalemia. Transcutaneous pacing provided cardiac pacing and stabilized the patient during the second episode. Thorough preoperative evaluation and prophylactic placement of temporary pacing or at least transcutaneous pacing are important for the avoidance and minimization of intraoperative complications in patients with sick sinus syndrome and with an AAI (atrial inhibited) pacemaker.

  10. Arrhythmia classification using SVM with selected features | Kohli ...

    African Journals Online (AJOL)

    The various types of arrhythmias in the cardiac arrhythmias ECG database chosen from University of California at Irvine (UCI) to train SVM include ischemic changes (coronary artery disease), old inferior myocardial infarction, sinus bradycardy, right bundle branch block, and others. ECG arrhythmia datasets are of generally ...

  11. Atrial natriuretic peptide in patients with heart failure and chronic atrial fibrillation : Role of duration of at atrial fibrillation

    NARCIS (Netherlands)

    Van Den Berg, MP; Crijns, HJGM; Van Veldhuisen, DJ; Van Gelder, IC; De Kam, PJ; Lie, KI

    The purpose of this study was to analyze the determinants of atrial natriuretic peptide level in patients with congestive heart failure and atrial fibrillation. In particular, the duration of atrial fibrillation was analyzed because atrial fibrillation per se might have a specific effect on atrial

  12. Pharmacological Treatment for Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Kaoru Sugi, MD PhD

    2005-01-01

    Full Text Available Pharmacological treatment for atrial fibrillation has a variety of purposes, such as pharmacological defibrillation, maintenance of sinus rhythm, heart rate control to prevent congestive heart failure and prevention of both cerebral infarction and atrial remodeling. Sodium channel blockers are superior to potassium channel blockers for atrial defibrillation, while both sodium and potassium channel blockers are effective in the maintenance of sinus rhythm. In general, digitalis or Ca antagonists are used to control heart rate during atrial fibrillation to prevent congestive heart failure, while amiodarone or bepridil also reduce heart rates during atrial fibrillation. Anticoagulant therapy with warfarin is recommended to prevent cerebral infarction and angiotensin converting enzyme antagonists or angiotensin II receptor blockers are also used to prevent atrial remodeling. One should select appropriate drugs for treatment of atrial fibrillation according to the patient's condition.

  13. Incidence and prognostic significance of new onset atrial fibrillation/flutter in acute pericarditis.

    Science.gov (United States)

    Imazio, Massimo; Lazaros, George; Picardi, Elisa; Vasileiou, Panagiotis; Orlando, Fabrizio; Carraro, Mara; Tsiachris, Dimitris; Vlachopoulos, Charalambos; Georgiopoulos, George; Tousoulis, Dimitrios; Belli, Riccardo; Gaita, Fiorenzo

    2015-09-01

    Data on the incidence of new onset atrial fibrillation and flutter (AF/f) in patients with acute pericarditis are limited. We sought to determine the incidence and prognostic significance of AF/f in this setting. Between January 2006 and June 2014, consecutive new cases of acute pericarditis were included in two urban referral centres for pericardial diseases. All new cases of AF/f defined as episodes lasting ≥30 s were recorded. Events considered during follow-up consisted of AF/f and pericarditis recurrence, cardiac tamponade, pericardial constriction and death. 822 consecutive new cases of acute pericarditis (mean age 53±15 years, 444 men) were analysed. AF/f was detected in 35 patients (4.3%, mean age 66.5±11.3 years, 18 men). Patients with AF/f were significantly older (p=0.017) and presented more frequently with pericardial effusion (ppericarditis onset in 91.4% of cases, lasted >24 h in 25.7% and spontaneously converted in 74.3% of patients. Underlying structural heart disease was present in 17% of AF/f cases. In a 30-month follow-up, patients with history of AF/f at the initial episode had a higher rate of arrhythmia occurrence (34.3% vs 0.9%, ppericarditis identifies a predisposed population to AF/f with a high recurrence risk (about 35%): in these patients, pericarditis may act as an arrhythmic trigger and oral anticoagulation should be seriously considered according to guidelines. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  14. Atrial Anti-Arrhythmic Effects of Heptanol in Langendorff-Perfused Mouse Hearts.

    Directory of Open Access Journals (Sweden)

    Gary Tse

    Full Text Available Acute effects of heptanol (0.1 to 2 mM on atrial electrophysiology were explored in Langendorff-perfused mouse hearts. Left atrial bipolar electrogram or monophasic action potential recordings were obtained during right atrial stimulation. Regular pacing at 8 Hz elicited atrial activity in 11 out of 11 hearts without inducing atrial arrhythmias. Programmed electrical stimulation using a S1S2 protocol provoked atrial tachy-arrhythmias in 9 of 17 hearts. In the initially arrhythmic group, 2 mM heptanol exerted anti-arrhythmic effects (Fisher's exact test, P 0.05, which led to increases in ERP/latency ratio from 1.4 ± 0.1 to 2.1 ± 0.2 and ERP/APD90 ratio from 1.0 ± 0.1 to 2.1 ± 0.2 (P 0.05, leaving both AERP/latency ratio (2.1 ± 0.3 vs. 1.9 ± 0.2; P > 0.05 and ERP/APD90 ratio (2.0 ± 0.2 vs. 2.1 ± 0.1; P > 0.05 unaltered. Lower heptanol concentrations (0.1, 0.5 and 1 mM did not alter arrhythmogenicity or the above parameters. The present findings contrast with known ventricular pro-arrhythmic effects of heptanol associated with decreased ERP/latency ratio, despite increased ERP/APD ratio observed in both the atria and ventricles.

  15. [New Treatment for Vascular Thrombosis Prevention in Patients With Atrial Fibrillation: Left Atrial Appendage Occlusion].

    Science.gov (United States)

    Lin, Chen-Wei; Wang, Shiao-Pei

    2017-06-01

    Atrial fibrillation (AF) is a common type of arrhythmia that increases significantly the risk of blood clots in the heart and of stroke. Therefore, stroke prevention is a key goal of AF treatment. In the past, patients were required to take anticoagulants for the remainder of their life, to regularly the monitor international normalized ratio (INR) of prothrombin time (PT), and to avoid possible negative interactions with various drugs and foods. Left atrial appendage occlusion (LAAO), a novel device and technique, was thus developed for AF patients with contraindications to anticoagulants and a high risk of bleeding. When using this technique, the occluder is placed on the left atrial appendage in order to effectively prevent blood stasis and thrombi accumulation. Transesophageal echocardiogram and computed tomography are conducted prior to the LAAO procedure, which is similar to the procedure used for cardiac catheterization. After the LAAO procedure, the patient remains in the intensive care unit (ICU), where vital signs, bleeding at the puncture site, and pericardial tamponade complications are monitored. Health education on daily activities, anticoagulant use, and regular follow-up should be given prior to hospital discharge. While LAAO may not reduce the incidence of stroke, the benefits of this procedure include a significant reduction in bleeding complications as compared to procedures that use oral anticoagulants. Further studies including long-term follow up and in-depth examinations of this procedure are necessary. The present article offers a reference for clinical staffs who are responsible for the care of patients treated using the LAAO procedure.

  16. Inhibitions of late INa and CaMKII act synergistically to prevent ATX-II-induced atrial fibrillation in isolated rat right atria.

    Science.gov (United States)

    Liang, Faquan; Fan, Peidong; Jia, Jessie; Yang, Suya; Jiang, Zhan; Karpinski, Serge; Kornyeyev, Dmytro; Pagratis, Nikos; Belardinelli, Luiz; Yao, Lina

    2016-05-01

    Increases in late Na(+) current (late INa) and activation of Ca(2+)/calmodulin-dependent protein kinase (CaMKII) are associated with atrial arrhythmias. CaMKII also phosphorylates Nav1.5, further increasing late INa. The combination of a CaMKII inhibitor with a late INa inhibitor may be superior to each compound alone to suppress atrial arrhythmias. Therefore, we investigated the effect of a CaMKII inhibitor in combination with a late INa inhibitor on anemone toxin II (ATX-II, a late INa enhancer)-induced atrial arrhythmias. Rat right atrial tissue was isolated and preincubated with either the CaMKII inhibitor autocamtide-2-related inhibitory peptide (AIP), the late INa inhibitor GS458967, or both, and then exposed to ATX-II. ATX-II increased diastolic tension and caused fibrillation of isolated right atrial tissue. AIP (0.3μmol/L) and 0.1μmol/L GS458967 alone inhibited ATX-II-induced arrhythmias by 20±3% (mean±SEM, n=14) and 34±5% (n=13), respectively, whereas the two compounds in combination inhibited arrhythmias by 81±4% (n=10, pATX-induced increase of diastolic tension. Consistent with the mechanical and electrical data, 0.3μmol/L AIP and 0.1μmol/L GS458967 each inhibited ATX-II-induced CaMKII phosphorylation by 23±3% and 32±4%, whereas the combination of both compounds inhibited CaMKII phosphorylation completely. The effects of an enhanced late INa to induce arrhythmic activity and activation of CaMKII in atria are attenuated synergistically by inhibitors of late INa and CaMKII. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Increased amount of atrial fibrosis in patients with atrial fibrillation secondary to mitral valve disease

    NARCIS (Netherlands)

    Geuzebroek, Guillaume S. C.; van Amersfoorth, Shirley C. M.; Hoogendijk, Mark G.; Kelder, Johannes C.; van Hemel, Norbert M.; de Bakker, Jacques M. T.; Coronel, Ruben

    2012-01-01

    Objective: Atrial fibrosis is related to atrial fibrillation but may differ in patients with mitral valve disease or lone atrial fibrillation. Therefore, we studied atrial fibrosis in patients with atrial fibrillation + mitral valve disease or with lone atrial fibrillation and compared it with

  18. Impact of Supraventricular Tachyarrhythmia in Patients With Inherited Cardiac Arrhythmia.

    Science.gov (United States)

    Ragab, Ahmed A Y; Houck, Charlotte A; van der Does, Lisette J M E; Lanters, Eva A H; Muskens, Agnes J Q M; de Groot, Natasja M S

    2017-12-01

    Supraventricular tachyarrhythmia (SVT), especially atrial fibrillation (AF), has been observed in patients with inherited cardiac arrhythmia (ICA). Data on the time course of SVT and the occurrence of SVT other than AF is limited. In this study, we examined the prevalence, co-existence, and the time course of different types of SVT in patients with various ICAs. In this retrospective study, we selected 393 patients (median 49 years, range 17 to 87, 57% male) from a cohort of patients visiting the outpatient clinic for cardiogenetic screening of ICA. Patients' medical records were examined for the occurrence of AF and other SVT. AF/SVT was found in 49 patients (12%, 31 male, 42 ± 17 years). Patients presenting with only AF (n = 12, 3%) were older than patients presenting with only SVT (n = 28, 7%), respectively 52 ± 18 versus 37 ± 14, p = 0.007. Nineteen patients (5%) had multiple episodes of either AF (n = 7, 2%) or SVT (n = 12, 3%). Alternating episodes of AF and SVT occurred in 9 patients (2%). Intervals between second and third AF episodes were significantly shorter than between first and second episodes (p = 0.02). An implantable cardioverter defibrillator (ICD) was implanted in 158 patients (40.2%) and 26 patients (16%) had inappropriate ICD shocks (SVT 25, AF 1), particularly those with multiple SVT episodes (p = 0.003). In patients with a variety of ICAs, episodes of AF/SVT occurred in 12%. In patients with multiple AF episodes, intervals between consecutive episodes became significantly shorter over time. AF/SVT episodes are associated with inappropriate ICD shocks and aggressive therapy of AF/SVT is therefore justified. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Cardiac Arrhythmias and Abnormal Electrocardiograms After Acute Stroke.

    Science.gov (United States)

    Ruthirago, Doungporn; Julayanont, Parunyou; Tantrachoti, Pakpoom; Kim, Jongyeol; Nugent, Kenneth

    2016-01-01

    Cardiac arrhythmias and electrocardiogram (ECG) abnormalities occur frequently but are often underrecognized after strokes. Acute ischemic and hemorrhagic strokes in some particular area of brain can disrupt central autonomic control of the heart, precipitating cardiac arrhythmias, ECG abnormalities, myocardial injury and sometimes sudden death. Identification of high-risk patients after acute stroke is important to arrange appropriate cardiac monitoring and effective management of arrhythmias, and to prevent cardiac morbidity and mortality. More studies are needed to better clarify pathogenesis, localization of areas associated with arrhythmias and practical management of arrhythmias and abnormal ECGs after acute stroke. Copyright © 2016 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  20. Predictive factors of atrial fibrillation after coronary artery bypass grafting.

    Science.gov (United States)

    Folla, Cynthia de Oliveira; Melo, Cinthia Cristina de Santana; Silva, Rita de Cassia Gengo E

    2016-01-01

    To analyze predictive demographic and perioperative variables of postoperative atrial fibrillation in patients who underwent exclusively coronary artery bypass grafting. This was a retrospective cohort. We randomly selected 105 medical records of patients who underwent exclusively coronary artery bypass grafting in 2014. Demographic, clinical (preoperative and immediate postoperative) data and related with surgical procedure were collected from medical records. The occurrence of postoperative atrial fibrillation was considered until the third day after the surgery. Variables were analyzed using descriptive and inferential statistics. To identify predictive factors of postoperative atrial fibrillation we used a decision tree model with Classification and Regression Trees algorithm. Atrial fibrillation incidence was 19.0% (n=20). Patients with left atrial >40.5mm and aged >64.5 years were more likely to develop the arrhythmia during the post-surgical period. Left atrial diameter and advanced age were predictive factors of atrial fibrillation in patients who underwent exclusively coronary artery bypass grafting. Analisar as variáveis demográficas e perioperatórias preditivas de fibrilação atrial pós-operatória em pacientes brasileiros submetidos exclusivamente à cirurgia de revascularização do miocárdio. Trata-se de coorte retrospectiva. A amostra foi constituída de 105 prontuários de pacientes submetidos exclusivamente à revascularização do miocárdio no ano de 2014, selecionados aleatoriamente. Dados demográficos, clínicos (préoperatórios e do pós-operatório imediato) e relacionados ao procedimento cirúrgico foram coletados por meio de consulta ao prontuário. A ocorrência de fibrilação atrial no pós-operatório foi considerada até o terceiro dia após a cirurgia. As variáveis foram analisadas por estatística descritiva e inferencial. Para identificar os fatores preditivos de fibrilação atrial no pós-operatório, utilizou-se um

  1. INTRACARDIAC ATRIAL DEFIBRILLATION

    Science.gov (United States)

    Dosdall, Derek J.; Ideker, Raymond E.

    2007-01-01

    Intravascular ventricular defibrillation and intravascular atrial defibrillation have many similarities, some of which are as follows. An important factor influencing the outcome of the shock is the potential gradient field created throughout the ventricles or the atria by the shock. A minimum potential gradient is required throughout the ventricles and probably the atria to defibrillate. The value of this minimum potential gradient is affected by several factors including the duration, tilt, and number of phases of the waveform. For shock strengths near the defibrillation threshold, earliest activation following failed shocks arises in a region in which the potential gradient is low. The defibrillation threshold energy can be decreased by adding a third and even a fourth defibrillation electrode in regions where the shock potential gradient is low for the shock field created by the first two defibrillation electrodes and giving two sequential shocks, each through a different set of electrodes. However, the addition of more electrodes and sequential shocks complicates both the device and its implantation. Since patients are conscious when the atrial defibrillation shock is given, they experience pain during the shock, which is one of the main drawbacks of intravascular atrial defibrillation. Unfortunately, the pain threshold for defibrillation shocks is so low that a shock of less than 1 Joule is uncomfortable and is not much less painful than shocks several times stronger. Therefore, even though electrode configurations exist that have lower atrial defibrillation threshold energy requirements than the atrial defibrillation threshold with standard defibrillation electrode configurations used in implantable cardioverter/defibrillators (ICDs) for ventricular defibrillation, they are not clinically practical because their shocks are almost as painful as with the standard ICD electrode configurations and they would cause the ICD to be more complicated and to take

  2. Profound sedation with propofol modifies atrial fibrillation dynamics.

    Science.gov (United States)

    Cervigón, Raquel; Moreno, Javier; Pérez-Villacastín, Julián; Castells, Francisco

    2013-09-01

    During atrial fibrillation (AF), multiple wandering propagation wavelets at high rates drift around both atria under controversial hierarchical models. Antiarrhythmic drugs modify the cardiac ionic currents supporting the fibrillation process within the atria, and can alter AF propagation dynamics and even terminate the arrhythmia. However, some other drugs, theoretically nonantiarrhythmic, may slightly block particular cardiac ionic currents through uncertain mechanisms in such a subtle way at regular heart rates that may have been pharmacologically overlooked. These potential effects might be better exposed at much higher activation rates as in AF, where atrial cells depolarize over 400 times per second. In this review, we aimed to compile and discuss results from several studies evaluating the net effect of profound sedation with propofol on atrial cells and atrioventricular (AV) conduction. Propofol is a very commonly used anesthetic agent, and its possible effect on AF dynamics has systematically not been taken into account in the myriad of clinical studies dealing with AF intracardiac recordings. The possible effect of sedation with propofol on AF was evaluated through the analysis of AF propagation patterns before and after its infusion in a series of patients submitted to pulmonary vein ablation. Effect on AV conduction will be discussed as well. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.

  3. Both hypothyroidism and hyperthyroidism increase atrial fibrillation inducibility in rats.

    Science.gov (United States)

    Zhang, Youhua; Dedkov, Eduard I; Teplitsky, Diana; Weltman, Nathan Y; Pol, Christine J; Rajagopalan, Viswanathan; Lee, Bianca; Gerdes, A Martin

    2013-10-01

    Evidence indicates that cardiac hypothyroidism may contribute to heart failure progression. It is also known that heart failure is associated with an increased risk of atrial fibrillation (AF). Although it is established that hyperthyroidism increases AF incidence, the effect of hypothyroidism on AF is unclear. This study investigated the effects of different thyroid hormone levels, ranging from hypothyroidism to hyperthyroidism on AF inducibility in thyroidectomized rats. Thyroidectomized rats with serum-confirmed hypothyroidism 1 month after surgery were randomized into hypothyroid (N=9), euthyroid (N=9), and hyperthyroid (N=9) groups. Rats received placebo, 3.3-mg l-thyroxine (T4), or 20-mg T4 pellets (60-day release form) for 2 months, respectively. At the end of treatment, hypothyroid, euthyroid, and hyperthyroid status was confirmed. Hypothyroid animals showed cardiac atrophy and reduced cardiac systolic and diastolic functions, whereas hyperthyroid rats exhibited cardiac hypertrophy and increased cardiac function. Hypothyroidism and hyperthyroidism produced opposite electrophysiological changes in heart rates and atrial effective refractory period, but both significantly increased AF susceptibility. AF incidence was 78% in hypothyroid, 67% in hyperthyroid, and the duration of induced AF was also longer, compared with 11% in the euthyroid group (all PHypothyroidism increased atrial interstitial fibrosis, but connexin 43 was not affected. Both hypothyroidism and hyperthyroidism lead to increased AF vulnerability in a rat thyroidectomy model. Our results stress that normal thyroid hormone levels are required to maintain normal cardiac electrophysiology and to prevent cardiac arrhythmias and AF.

  4. Complications associated with catheter ablation of atrial fibrillation.

    Science.gov (United States)

    Dhruvakumar, S; Gerstenfeld, E P

    2007-06-01

    Atrial fibrillation is the most common clinical arrhythmia, affecting millions of people worldwide and utilizing billions of dollars annually in heath care costs associated with the disease. Catheter based ablation, centering around the electrical isolation of the pulmonary veins, has emerged as a viable treatment option for patients with symptomatic paroxysmal or persistent atrial fibrillation. Because of the complex nature of the procedure, there are a number of potential complications which can occur which are related to problems with vascular access, mechanical complications resulting from catheter manipulation within the heart, cardioembolic complications, and complications arising from the effects of radiofrequency ablations in the left atrium. The most frequent complications arise from pseudoaneurysms, arterio-venous fistulas, hematomas, neurologic events (stroke and transient ischemic attacks), and pericardial effusion/tamponade. An evolving understanding of the risks of the procedure have helped to minimize complications by changing ablation strategies to avoid lesion delivery within the veins, emphasizing careful attention during the procedure to anticoagulation, utilizing intracardiac ultrasound and electroanatomic mapping systems for better visualization of intracardiac structures, and recognizing complications promptly during and after the procedure. Hopefully, improved techniques in the future will help to further improve the safety of catheter ablation of atrial fibrillation to allow for continued growth of this procedure.

  5. Triggering Artefacts

    DEFF Research Database (Denmark)

    Mogensen, Preben Holst; Robinson, Mike

    1995-01-01

    The paper presents a general critique of the use of conceptual frameworks in design, illustrated by the well known synchronous/asynchronous, co-located/non-co-located framework. It argues that while frameworks are a necessary and inevitable starting point for design, the business of tailoring...... and adapting them to specific situations need not be ad hoc.Triggering artefacts are a way of systematically challenging both designers' preunderstandings and the conservatism of work practice. Experiences from the Great Belt tunnel and bridge project are used to illustrate howtriggering artefacts change...

  6. Apical hypertrophic cardiomyopathy with hemodynamically unstable ventricular arrhythmia – Atypical presentation

    Directory of Open Access Journals (Sweden)

    Hemant Chaturvedi

    2016-09-01

    Full Text Available We present a patient with asymptomatic apical hypertrophic cardiomyopathy (AHCM who recently developed cardiac arrhythmias, and shortly discuss the diagnostic modalities, differential diagnosis, and treatment strategy for this condition. AHCM is a rare form of hypertrophic cardiomyopathy, which usually involves the apex of the left ventricle. AHCM can occur with varied presentations such as chest pain, palpitations, dyspnea, syncope, atrial fibrillation, myocardial infarction, embolic events, ventricular fibrillation, and congestive heart failure. The most peculiar electrocardiogram findings are giant T-waves inversion in the precordial leads with left ventricular (LV hypertrophy. A transthoracic echocardiogram is the initial diagnostic modality in the evaluation of AHCM and shows hypertrophy of the LV apex. Other diagnostic modalities, including left ventriculography, multislice spiral computed tomography, and cardiac magnetic resonance imagings, are also valuable tools. Medications used to manage include verapamil, beta-blockers, and antiarrhythmic agents. An implantable cardioverter defibrillator (ICD is recommended for high-risk patients.

  7. INTRAOPERATIVE RADIOFREQUENCY AND CRYOABLATION FOR ATRIAL FIBRILLATION IN PATIENTS WITH VALVULAR HEART DISEASE

    Directory of Open Access Journals (Sweden)

    N. Maghamipour N. Safaie

    2007-05-01

    Full Text Available Patients with valvular heart disease and suffering atrial fibrillation of more than 12 months duration have a low probability of remaining in sinus rhythm after valve surgery alone. We performed intra-operative radiofrequency ablation or cryoablation as an alternative to surgical maze ІІІ procedure to create linear lesion lines for conversion of this arrhythmia to sinus rhythm. A total of 30 patients with valvular heart disease and chronic persistent atrial fibrillation underwent different combinations of valve surgery and concomitant maze procedure with radiofrequency or cryo probes. These patients aged 48.10 ± 9.84 years in radiofrequency ablation group and 51.10 ± 13.93 years in cryoablation group. Both atrial ablation with radiofrequency probes, needed 26.15 ± 3.67 min extra ischemic time and ablation by mean of cryo-probes needed an extra ischemic time of 29.62 ± 4.27 min. There was one in hospital death postoperatively because of respiratory failure but no other complication. 6 months after the operation, among 30 patients with both atrial ablations, 25 patients were in sinus rhythm, no patient had junctional rhythm and 5 patients had persistent atrial fibrillation. At 12 months follow up, freedom from atrial fibrillation was 85% in radiofrequency group and 80% in cryo group. Doppler echocardiography in these patients demonstrated atrial contractility in 70% of the patients. Intraoperative radiofrequency or cryo-ablation of both atriums are effective and less invasive alternatives for the original maze procedure to eliminate the atrial fibrillation, and can be done in patients with valvular heart disease without increasing the risk of operation.

  8. Paroxysmal atrial fibrillation in seven dogs with presumed neurally-mediated syncope.

    Science.gov (United States)

    Porteiro Vázquez, D M; Perego, M; Santos, L; Gerou-Ferriani, M; Martin, M W S; Santilli, R A

    2016-03-01

    To document the electrocardiographic findings of vagally-induced paroxysmal atrial fibrillation following a presumed reflex syncopal episode in the dog. Seven dogs with a syncopal episode followed by a paroxysm of atrial fibrillation recorded on a 24-hour Holter. Twenty-four hour Holter monitors were retrospectively reviewed, analysing the cardiac rhythm associated with syncopal events. Each recording was analysed from 10 min before the syncopal episode to until 10 min after a normal sinus rhythm had returned. Nine episodes were recorded in seven dogs, with one patient experiencing three events during one Holter recording. Five of the seven dogs presented with underlying structural heart disease. In two the syncopal episodes occurred following exercise, two associated with coughing and three were during a period of rest. All dogs had documented on the Holter recording a rhythm abnormality during syncope. The most common finding leading up to the syncopal event was development of a progressive sinus bradycardia, followed by sinus arrest interrupted by a ventricular escape rhythm and then ventricular arrest. This was then followed by an atrial fibrillation. The atrial fibrillation was paroxysmal in seven recordings and persistent in two. In two dogs, the atrial fibrillation reorganised into self-limiting runs of atypical atrial flutter. This combination of electrocardiographic arrhythmias are probably caused by an inappropriate parasympathetic stimulation initiating a reflex or neurally-mediated syncope, with abnormal automaticity of the sinus node and of the subsidiary pacemaker cells and changes in the electrophysiological properties of the atrial muscle, which promoted the paroxysmal atrial fibrillation. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Arrhythmia susceptibility in senescent rat hearts

    Directory of Open Access Journals (Sweden)

    Stefano Rossi

    2014-01-01

    Full Text Available Cardiovascular disease increases with age as well as alterations of cardiac electrophysiological properties, but a detailed knowledge about changes in cardiac electrophysiology relevant to arrhythmogenesis in the elderly is relatively lacking. The aim of this study was to determine specific age-related changes in electrophysiological properties of the ventricles which can be related to a structural-functional arrhythmogenic substrate. Multiple epicardial electrograms were recorded on the ventricular surface of in vivo control and aged rats, while arrhythmia vulnerability was investigated by premature stimulation protocols. Single or multiple ectopic beats and sustained ventricular arrhythmias were frequently induced in aged but not in control hearts. Abnormal ventricular activation patterns during sinus rhythm and unchanged conduction velocity during point stimulation in aged hearts suggest the occurrence of impaired impulse conduction through the distal Purkinje system that might create a potential reentry substrate.

  10. Influence of coffee and caffeine consumption on atrial fibrillation in hypertensive patients.

    Science.gov (United States)

    Mattioli, A V; Farinetti, A; Miloro, C; Pedrazzi, P; Mattioli, G

    2011-06-01

    Coffee and caffeine are widely consumed in Western countries. Little information is available on the influence of coffee and caffeine consumption on atrial fibrillation (AF) in hypertensive patients. We sought to investigate the relationship between coffee consumption and atrial fibrillation with regard to spontaneous conversion of arrhythmia. A group of 600 patients presenting with a first known episode of AF was investigated, and we identified 247 hypertensive patients. The prevalence of nutritional parameters was assessed with a food frequency questionnaire. Coffee and caffeine intake were specifically estimated. Left ventricular hypertrophy was evaluated by electrocardiogram (ECG) and echocardiogram. Coffee consumption was higher in normotensive patients. High coffee consumers were more frequent in normotensive patients compared with hypertensive patients. On the other hand, the intake of caffeine was similar in hypertensive and normotensive patients, owing to a higher intake in hypertensive patients from sources other than coffee. Within normotensive patients, we report that non-habitual and low coffee consumers showed the highest probability of spontaneous conversion (OR 1.93 95%CI 0.88-3.23; p=0.001), whereas, within hypertensive patients, moderate but not high coffee consumers had the lowest probability of spontaneous conversion (OR 1.13 95%CI 0.67-1.99; p=0.05). Coffee and caffeine consumption influence spontaneous conversion of atrial fibrillation. Normotensive non-habitual coffee consumers are more likely to convert arrhythmia within 48h from the onset of symptoms. Hypertensive patients showed a U-shaped relationship between coffee consumption and spontaneous conversion of AF, moderate coffee consumers were less likely to show spontaneous conversion of arrhythmia. Patients with left ventricular hypertrophy showed a reduced rate of spontaneous conversion of arrhythmia. Copyright © 2009 Elsevier B.V. All rights reserved.

  11. Dronedarone: an emerging therapy for atrial fibrillation.

    Science.gov (United States)

    Rosei, Enrico Agabiti; Salvetti, Massimo

    2010-06-01

    Atrial fibrillation (AF) is a common arrhythmia, with a prevalence ranging from 0.1% to 9.0% at different ages, and is associated with increased cardiovascular events and mortality. A significant increase in the prevalence of the disease is expected to occur in the coming years as a consequence of the aging of the population and advances in the management of coronary artery disease and heart failure. Effective rhythm control may be difficult to obtain in a significant proportion of patients with AF. The limited efficacy and the possible adverse effects of antiarrhythmic drugs has led researchers to focus their attention on new molecules, in a search of compounds with antiarrhythmic efficacy and a more favourable safety profile. Among several new drugs developed for the management of AF, dronedarone, a benzofuran derivative that shares many of the antiarrhythmic properties of amiodarone, but with a more favourable safety profile, seems particularly promising. The drug is noniodinated, has less lipophilicity, reaches therapeutic concentrations over a shorter period of time and has lower tissue accumulation. Dronedarone, similarly to amiodarone, exhibits electrophysiologic characteristics of all 4 Vaughan Williams classes. Clinical studies have shown that dronedarone effectively reduces ventricular rate, may prevent or delay the recurrence of AF, and may reduce cardiovascular morbidity and mortality in patients with AF or atrial flutter. The drug has an overall good safety profile, in particular with low pulmonary and thyroid toxicity. An important exception is represented by patients with unstable haemodynamic conditions, in which the use of dronedarone has been found to be associated with an increase in mortality. Dronedarone has been recently approved for clinical use by the Food and Drug Administration and by the European Medicines Agency. Further results from trials and clinical use will better define the efficacy and safety profile of dronedarone in AF compared

  12. Multifocal Atrial Tachycardia in 2 Children

    Directory of Open Access Journals (Sweden)

    Ming-Yun Hsieh

    2006-09-01

    Full Text Available The incidence of multifocal atrial tachycardia (MAT is very low and accounts for less than 1% of supraventricular tachycardia in infants and children. In this report, the clinical characteristics, medical treatment and outcome of MAT in 2 children are described. The first patient presented with tachycardia and respiratory failure since the day after birth. First, he received amiodarone, propranolol, and digoxin and then amiodarone alone. The heart rhythm converted to sinus rhythm 2 weeks after hospitalization. Although nonsustained MAT was occasionally observed when the infant suffered from pulmonary infection, the frequency of recurrent MAT decreased as the infant grew up. The second patient was a 5-year-old girl. She had congenital heart disease with double outlets of right ventricle (DORV, patent ductus arte-riosus, coarctation of aorta, and ventricular and atrial septal defects. She underwent total correction at the age of 4 years. MAT was noted 3 months after the operation with the presentation of congestive heart failure. The heart rate slowed down and returned to normal sinus rhythm within several hours after amiodarone use. The symptoms and signs of congestive heart failure also disappeared. The patient took amiodarone regularly, and no tachycardia was detected during the follow-up period. MAT is considered to be a relatively benign arrhythmia with likely good outcome if there is no severe underlying illness. It can be well controlled under appropriate drugs, and a long period of follow-up is suggested. If pharmacologic intervention is required, we suggest that amiodarone may be an excellent choice.

  13. [Electrophysiological findings and ablation strategies in patients with atrial tachyarrhythmias after left atrial circumferential ablation in the treatment of atrial fibrillation].

    Science.gov (United States)

    Chen, Ming-long; Yang, Bing; Xu, Dong-jie; Zou, Jian-gang; Shan, Qi-jun; Chen, Chun; Chen, Hong-wu; Li, Wen-qi; Cao, Ke-jiang

    2007-02-01

    Holter recording of atrial premature contractions; 2 of them with permanent AF became paroxysmal in one, and still in AF in the other. Reconduction between the left atrium and the pulmonary veins is the dominant factor for post-LACA ATAs and AF recurrence. Other forms of atrial tachycardias or supraventricular tachycardias may coexist with AF or sometimes trigger AF. LACA can not sufficiently modify AF substrate in some permanent AF patients.

  14. Single-Nucleotide Variations in Cardiac Arrhythmias: Prospects for Genomics and Proteomics Based Biomarker Discovery and Diagnostics

    Science.gov (United States)

    Abunimer, Ayman; Smith, Krista; Wu, Tsung-Jung; Lam, Phuc; Simonyan, Vahan; Mazumder, Raja

    2014-01-01

    Cardiovascular diseases are a large contributor to causes of early death in developed countries. Some of these conditions, such as sudden cardiac death and atrial fibrillation, stem from arrhythmias—a spectrum of conditions with abnormal electrical activity in the heart. Genome-wide association studies can identify single nucleotide variations (SNVs) that may predispose individuals to developing acquired forms of arrhythmias. Through manual curation of published genome-wide association studies, we have collected a comprehensive list of 75 SNVs associated with cardiac arrhythmias. Ten of the SNVs result in amino acid changes and can be used in proteomic-based detection methods. In an effort to identify additional non-synonymous mutations that affect the proteome, we analyzed the post-translational modification S-nitrosylation, which is known to affect cardiac arrhythmias. We identified loss of seven known S-nitrosylation sites due to non-synonymous single nucleotide variations (nsSNVs). For predicted nitrosylation sites we found 1429 proteins where the sites are modified due to nsSNV. Analysis of the predicted S-nitrosylation dataset for over- or under-representation (compared to the complete human proteome) of pathways and functional elements shows significant statistical over-representation of the blood coagulation pathway. Gene Ontology (GO) analysis displays statistically over-represented terms related to muscle contraction, receptor activity, motor activity, cystoskeleton components, and microtubule activity. Through the genomic and proteomic context of SNVs and S-nitrosylation sites presented in this study, researchers can look for variation that can predispose individuals to cardiac arrhythmias. Such attempts to elucidate mechanisms of arrhythmia thereby add yet another useful parameter in predicting susceptibility for cardiac diseases. PMID:24705329

  15. Single-Nucleotide Variations in Cardiac Arrhythmias: Prospects for Genomics and Proteomics Based Biomarker Discovery and Diagnostics

    Directory of Open Access Journals (Sweden)

    Ayman Abunimer

    2014-03-01

    Full Text Available Cardiovascular diseases are a large contributor to causes of early death in developed countries. Some of these conditions, such as sudden cardiac death and atrial fibrillation, stem from arrhythmias—a spectrum of conditions with abnormal electrical activity in the heart. Genome-wide association studies can identify single nucleotide variations (SNVs that may predispose individuals to developing acquired forms of arrhythmias. Through manual curation of published genome-wide association studies, we have collected a comprehensive list of 75 SNVs associated with cardiac arrhythmias. Ten of the SNVs result in amino acid changes and can be used in proteomic-based detection methods. In an effort to identify additional non-synonymous mutations that affect the proteome, we analyzed the post-translational modification S-nitrosylation, which is known to affect cardiac arrhythmias. We identified loss of seven known S-nitrosylation sites due to non-synonymous single nucleotide variations (nsSNVs. For predicted nitrosylation sites we found 1429 proteins where the sites are modified due to nsSNV. Analysis of the predicted S-nitrosylation dataset for over- or under-representation (compared to the complete human proteome of pathways and functional elements shows significant statistical over-representation of the blood coagulation pathway. Gene Ontology (GO analysis displays statistically over-represented terms related to muscle contraction, receptor activity, motor activity, cystoskeleton components, and microtubule activity. Through the genomic and proteomic context of SNVs and S-nitrosylation sites presented in this study, researchers can look for variation that can predispose individuals to cardiac arrhythmias. Such attempts to elucidate mechanisms of arrhythmia thereby add yet another useful parameter in predicting susceptibility for cardiac diseases.

  16. [Silent myocardial ischemia and exercise-induced arrhythmia detected by the exercise test in the total health promotion plan (THP)].

    Science.gov (United States)

    Iwane, M; Shibe, Y; Itoh, K; Kinoshita, F; Kanagawa, Y; Kobayashi, M; Mugitani, K; Ohta, M; Ohata, H; Yoshikawa, A; Ikuta, Z; Nakamura, Y; Mohara, O

    2001-03-01

    We investigated the prevalence and characteristics of ischemic heart disease especially silent myocardial ischemia (SMI) and arrhythmia in need of careful observation in the exercise stress tests in the Total Health Promotion Plan (THP), which was conducted between 1994-96 for the purpose of measuring cardiopulmonary function. All workers (n = 4,918, 4,426 males) aged 18-60 yr old in an occupational field were studied. Exercise tests with an ergometer were performed by the LOPS protocol, in which the maximal workload was set up as a presumed 70-80% maximal oxygen intake, or STEP (original multistage protocol). ECG changes were evaluated with a CC5 lead. Two hundred and fifteen people refused the study because of a common cold, lumbago and so on. Of 4,703 subjects, 17 with abnormal rest ECG and 19 with probable anginal pain were excluded from the exercise tests. Of 4,667 who underwent the exercise test, 37 (0.79%) had ischemic ECG change, and 155 (3.32%) had striking arrhythmia. These 228 subjects then did a treadmill exercise test with Bruce protocol. Twenty-two (0.47% of 4,703) showed positive ECG change, 9 (0.19%) of 22 had abnormal findings on a 201Tl scan. 8 (0.17%) were diagnosed as SMI (Cohn I), in which the prevalence of hypertension, hyperlipidemia, diabetes mellitus, smoker and positive familial history of ischemic heart disease was greater than that of all subjects. In a 15-30 month follow up, none has developed cardiac accidents. Exercise-induced arrhythmia was detected in 11 (0.23%) subjects. Four were non-sustained ventricular tachycardia without any organic disease, 4 were ventricular arrhythmia based on cardiomyopathy detected by echocardiography, 2 were atrial fibrillation and another was WPW syndrome. It is therefore likely that the ergometer exercise test in THP was effective in preventing sudden death caused by ischemic heart disease or striking arrhythmia.

  17. Aconite poisoning with arrhythmia and shock

    OpenAIRE

    Tak, Sandeep; Lakhotia, Manoj; Gupta, Alok; Sagar, Amit; Bohra, Gopal; Bajari, Rajesh

    2016-01-01

    •Use of Ayurvedic medicines by a layman as self-treatment with an assumption that Ayurvedic/natural medicines are free of side effects.•Availability of potentially toxic substance without regulation or prescription.•Possibility of missing the diagnosis altogether if treating physicians/cardiologists do not specifically ask about the use of alternative medicines. This case report again highlights importance of taking detailed treatment history particularly in patients with arrhythmia.•Successf...

  18. Cellular Mechanisms of Calcium-Mediated Triggered Activity

    Science.gov (United States)

    Song, Zhen

    Life-threatening cardiac arrhythmias continue to pose a major health problem. Ventricular fibrillation, which is a complex form of electrical wave turbulence in the lower chambers of the heart, stops the heart from pumping and is the largest cause of natural death in the United States. Atrial fibrillation, a related form of wave turbulence in the upper heart chambers, is in turn the most common arrhythmia diagnosed in clinical practice. Despite extensive research to date, mechanisms of cardiac arrhythmias remain poorly understood. It is well established that both spatial disorder of the refractory period of heart cells and triggered activity (TA) jointly contribute to the initiation and maintenance of arrhythmias. TA broadly refers to the abnormal generation of a single or a sequence of abnormal excitation waves from a small submillimeter region of the heart in the interval of time between two normal waves generated by the heart's natural pacemaker (the sinoatrial node). TA has been widely investigated experimentally and occurs in several pathological conditions where the intracellular concentration of free Ca2+ ions in heart cells becomes elevated. Under such conditions, Ca2+ can be spontaneously released from intracellular stores, thereby driving an electrogenic current that exchanges 3Na+ ions for one Ca2+ ion across the cell membrane. This current in turn depolarizes the membrane of heart cells after a normal excitation. If this calcium-mediated "delayed after depolarization'' (DAD) is sufficiently large, it can generate an action potential. While the arrhythmogenic importance of spontaneous Ca2+ release and DADs is well appreciated, the conditions under which they occur in heart pathologies remain poorly understood. Calcium overload is only one factor among several other factors that can promote DADs, including sympathetic nerve stimulation, different expression levels of membrane ion channels and calcium handling proteins, and different mutations of those

  19. Unilateral atrial fibrillation - how common is atrial divorce?

    Science.gov (United States)

    Ker, J

    2017-06-01

    Atrial fibrillation is the most common pathologic supraventricular tachycardia. It has many causes, is an expensive disease, impairs quality of life and leads to an increased risk of death. Atrial dissociation is characterised by the presence of two independent sets of P-waves. This peculiar abnormality may give rise to the scenario where one atrium is in atrial fibrillation while the other is in sinus rhythm. This is the first published case of atrial dissociation where the phenomenon is demonstrated by transmitral and transtricuspid pulsed wave Doppler.

  20. RIESGO DE ARRITMIAS E HIPERTENSIÓN ARTERIAL / Risk of Arrhythmias and hypertension

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    Raimundo Carmona Puerta

    2012-03-01

    Full Text Available Resumen La mayor prevalencia de fibrilación auricular se duplica en pacientes con cardiopatía hipertensiva. En el estudio Framingham se encontraron como factores de riesgo: la hipertensión, la máxima duración y dispersión de la onda P del electrocardiograma, el tamaño de la aurícula y la masa ventricular izquierda. El sistema renina-angiotensina-aldosterona es responsable de la inflamación y los cambios estructurales que justifican la aparición de arritmias en el paciente hipertenso. La presencia de arritmias ventriculares, desde complejos ventriculares prematuros hasta la taquicardia ventricular, se ha demostrado entre un 10 - 27 % en los pacientes afectados, porcentaje que disminuye mientras más grave es la arritmia. Se han resumido los siguientes marcadores incruentos de riesgo para presentar arritmias ventriculares: dispersión y variabilidad del intervalo QT, presencia de potenciales tardíos, variabilidad de la frecuencia cardíaca, y morfología anormal y alternancia de la onda T. Todos ellos relacionados con cambios anátomo-estructurales de la pared ventricular, que afectan el potencial de acción. La importancia de conocer la epidemiología, fisiopatología, y los marcadores incruentos de riesgo de presentar arritmias en el paciente hipertenso, ofrece un camino para la aplicación de una correcta terapéutica en el control de las cifras de presión arterial y regresión de la hipertrofia, como lo han demostrado los fármacos inhibidores del sistema renina-angiotensina-aldosterona, que disminuyen el riesgo de arritmias. / Abstract The higher prevalence of atrial fibrillation is doubled in patients with hypertensive heart disease. In the Framingham study, the following risk factors were found: hypertension, maximum P wave duration and dispersion of the electrocardiogram, atrial size and left ventricular mass. The renin-angiotensin-aldosterone system is responsible for the inflammation and the structural changes that justify

  1. Incorporating Stroke and Bleeding Risk Stratification Tools into Atrial Fibrillation Management Making Sense of the Alphabet Soup.

    Science.gov (United States)

    Deering, Thomas F

    2017-01-01

    Atrial fibrillation (AF) is a common arrhythmia managed by many physicians in a variety of clinical settings. One of the most important clinical decisions related to effective AF management centers upon the need to perform accurate thromboembolic risk stratification followed by effective management decisions that align with established guidelines. This manuscript will review the present state of the art and provide guidance to physicians to enhance patient outcomes.

  2. Amiodarone-Induced Third Degree Atrioventricular Block and Extreme QT Prolongation Generating Torsade Des Pointes in Paroxysmal Atrial Fibrillation

    OpenAIRE

    Sequeira, Orlando Robert; Aquino, Nelson Javier; Gómez, Nancy Beatriz; García, Laura Beatriz; Cáceres, Cristina; Lovera, Oscar A; Centurión, Osmar Antonio

    2016-01-01

    Amiodarone is still the most potent antiarrhythmic drug in the prevention of life threatening ventricular arrhythmias and demonstrates a very low incidence of torsade de pointes. An unusual case of an 81-year-old woman who developed serious abnormalities of the conduction system of the heart and torsade des pointes during intravenous infusion of amiodarone for the treatment of paroxysmal atrial fibrillation is described. To the best of our knowledge, this is the first case showing an associat...

  3. Arrhythmia Diagnosis Following an ICD Shock.

    Directory of Open Access Journals (Sweden)

    Roy M. John

    2001-10-01

    Full Text Available Stored electrograms show atrial fibrillation with rapid ventricular rates (top panel. Sufficient numbers of RR intervals meet the tachycardia detection criteria initiating a train of anti-tachycardia pacing by the ICD (after the 8th electrogram in the second panel. This provokes rapid monomorphic ventricular tachycardia (note that the electrogram morphology is different from that during atrial fibrillation which enters the fibrillation detection zone leading to an ICD shock (after the 3rd electrogram in the 4th panel. Sinus rhythm is restored. Note the 5th and 11th electrograms in the 4th panel have different morphology from sinus rhythm electrogram following shock indicating PVCs. There is no evidence for ICD malfunction. Induction of ventricular tachycardia by attempted anti-tachycardia pacing is a pro-arrhythmic effect of ICD therapy.

  4. Firearm trigger assembly

    Science.gov (United States)

    Crandall, David L.; Watson, Richard W.

    2010-02-16

    A firearm trigger assembly for use with a firearm includes a trigger mounted to a forestock of the firearm so that the trigger is movable between a rest position and a triggering position by a forwardly placed support hand of a user. An elongated trigger member operatively associated with the trigger operates a sear assembly of the firearm when the trigger is moved to the triggering position. An action release assembly operatively associated with the firearm trigger assembly and a movable assembly of the firearm prevents the trigger from being moved to the triggering position when the movable assembly is not in the locked position.

  5. Assessment of atrial electromechanical delay and left atrial mechanical functions in patients with psoriasis vulgaris.

    Science.gov (United States)

    Aksan, Gökhan; Nar, Gökay; Soylu, Korhan; İnci, Sinan; Yuksel, Serkan; Ocal, Hande Serra; Yuksel, Esra Pancar; Gulel, Okan

    2015-04-01

    Increased frequency of atrial fibrillation (AF) has been demonstrated in psoriasis cases. Prolongation of the duration of atrial electromechanical delay (AEMD) is a well-known characteristic of the atrium, which is vulnerable to AF. In the current study, our aims are to investigate AEMD durations and mechanical functions of the left atrium (LA) in patients with psoriasis. A total of 90 patients, 45 with psoriasis vulgaris and 45 as the control group, were included in the study. Atrial electromechanical coupling (PA) and intra- and inter-atrial electromechanical delay (IA-AEMD) were measured with tissue Doppler echocardiography. P-wave dispersion (PWD) was calculated from the 12-lead electrocardiogram. The severity of the disease was evaluated by the Psoriasis Area and Severity Index. The durations of PA lateral and PA septal were significantly high in the psoriasis group when compared with the control group (47.7 ± 9.8 vs. 57.1 ± 8.4 msec, P < 0.001 and 38.6 ± 9.9 vs. 43.6 ± 8 msec, P = 0.016, respectively). The durations of IA-AEMD, intra-right electromechanical delay, and intra-left electromechanical delay in the psoriasis group were significantly prolonged compared with the control group (15.2 ± 4.1 vs. 21.7 ± 5.6 msec, P < 0.001; 6 ± 2.5 vs. 8.7 ± 2.7 msec, P < 0.001; and 9.1 ± 3.9 vs. 13.5 ± 5.2 msec, P < 0.001; respectively). PWD was significantly higher in patients with psoriasis vulgaris compared with controls (36.1 ± 7.9 vs. 40.2 ± 9.1 msec, P = 0.043). In the present study, we found prolongation in the durations of AEMD and PWD in the psoriasis group compared with the control group. These results might be an early predictor of AF and other arrhythmias. © 2014, Wiley Periodicals, Inc.

  6. Safety and efficacy of vernakalant for acute cardioversion of atrial fibrillation: an update.

    Science.gov (United States)

    Tsuji, Yukiomi; Dobrev, Dobromir

    2013-01-01

    Intravenous vernakalant has recently been approved in Europe as an atrial-selective antiarrhythmic drug for the conversion of recent-onset atrial fibrillation (AF). It inhibits atrial-selective K(+) currents (I(K,ACh) and I(Kur)) and causes rate-dependent atrial-predominant Na(+) channel block, with only a small inhibitory effect on the rapid delayed rectifier K(+) current (I(Kr)) in the ventricle. Due to its atrial-selective properties, vernakalant prolongs the effective refractory period of the atria with minimal effects on the ventricles, being associated with a low proarrhythmic risk for torsades de pointes arrhythmias. Five pivotal clinical trials consistently demonstrated that vernakalant rapidly terminates AF with stable maintenance of sinus rhythm for up to 24 hours. A head-to-head comparative trial showed that the 90-minute conversion rate of vernakalant was substantially higher than that of amiodarone. Initially, a longer-acting oral formulation of vernakalant was shown to be effective and safe in preventing AF recurrence after cardioversion in a Phase IIb study. However, the clinical studies testing oral vernakalant for maintenance of sinus rhythm after AF cardioversion were prematurely halted for undisclosed reasons. This review article provides an update on the safety and efficacy of intravenous vernakalant for the rapid cardioversion of AF.

  7. The caregiver role in thromboprophylaxis management in atrial fibrillation: a literature review.

    Science.gov (United States)

    Ferguson, Caleb; Inglis, Sally C; Newton, Phillip J; Middleton, Sandy; Macdonald, Peter S; Davidson, Patricia M

    2015-04-01

    Atrial fibrillation is a common arrhythmia and a risk factor for adverse events including stroke. People living with atrial fibrillation are commonly elderly and have multiple comorbidities. The role of a caregiver in supporting the individual to manage a chronic and complex condition has received limited attention. This review aims to summarize available information on the caregiver role in atrial fibrillation, specifically in promoting adherence to thromboprophylaxis and evidence for strategies to support and enable the caregiver. A review of electronic databases and search engines was undertaken including Medline, Scopus and CINAHL. The search terms 'atrial fibrillation', 'anticoagulation', 'carer', 'caregiver', 'family support' were used. Dates searched were from January 1990 to November 2012. The review found limited original clinical research studies. The majority of the literature identified in the initial search included review papers and work which recommends the inclusion of the caregiver in the care of patients with atrial fibrillation but limited empirical evidence. Caregivers have an essential role to play in advocacy, family centred care and shared decision-making. This may influence thromboprophylaxis treatment choices and potentially adherence. Assessment of caregiver needs and support should be central to patient assessment and care planning. There is a need for clinical intervention studies which more target and address the caregiver role. © The European Society of Cardiology 2014.

  8. Red Wine, Resveratrol and Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Laura Siga Stephan

    2017-10-01

    Full Text Available Atrial fibrillation (AF is a common cardiac arrhythmia that is associated with increased risk for cardiovascular disease and overall mortality. Excessive alcohol intake is a well-known risk factor for AF, but this correlation is less clear with light and moderate drinking. Besides, low doses of red wine may acutely prolong repolarization and slow cardiac conduction. Resveratrol, a bioactive polyphenol found in grapes and red wine, has been linked to antiarrhythmic properties and may act as an inhibitor of both intracellular calcium release and pathological signaling cascades in AF, eliminating calcium overload and preserving the cardiomyocyte contractile function. However, there are still no clinical trials at all that prove that resveratrol supplementation leads to improved outcomes. Besides, no observational study supports a beneficial effect of light or moderate alcohol intake and a lower risk of AF. The purpose of this review is to briefly describe possible beneficial effects of red wine and resveratrol in AF, and also present studies conducted in humans regarding chronic red wine consumption, resveratrol, and AF.

  9. Atrial Fibrillation Ablation in Systolic Dysfunction: Clinical and Echocardiographic Outcomes

    Directory of Open Access Journals (Sweden)

    Tasso Julio Lobo

    2015-01-01

    Full Text Available Background: Heart failure and atrial fibrillation (AF often coexist in a deleterious cycle. Objective: To evaluate the clinical and echocardiographic outcomes of patients with ventricular systolic dysfunction and AF treated with radiofrequency (RF ablation. Methods: Patients with ventricular systolic dysfunction [ejection fraction (EF <50%] and AF refractory to drug therapy underwent stepwise RF ablation in the same session with pulmonary vein isolation, ablation of AF nests and of residual atrial tachycardia, named "background tachycardia". Clinical (NYHA functional class and echocardiographic (EF, left atrial diameter data were compared (McNemar test and t test before and after ablation. Results: 31 patients (6 women, 25 men, aged 37 to 77 years (mean, 59.8±10.6, underwent RF ablation. The etiology was mainly idiopathic (19 p, 61%. During a mean follow-up of 20.3±17 months, 24 patients (77% were in sinus rhythm, 11 (35% being on amiodarone. Eight patients (26% underwent more than one procedure (6 underwent 2 procedures, and 2 underwent 3 procedures. Significant NYHA functional class improvement was observed (pre-ablation: 2.23±0.56; postablation: 1.13±0.35; p<0.0001. The echocardiographic outcome also showed significant ventricular function improvement (EF pre: 44.68%±6.02%, post: 59%±13.2%, p=0.0005 and a significant left atrial diameter reduction (pre: 46.61±7.3 mm; post: 43.59±6.6 mm; p=0.026. No major complications occurred. Conclusion: Our findings suggest that AF ablation in patients with ventricular systolic dysfunction is a safe and highly effective procedure. Arrhythmia control has a great impact on ventricular function recovery and functional class improvement.

  10. Atrial Fibrillation Ablation in Systolic Dysfunction: Clinical and Echocardiographic Outcomes

    Science.gov (United States)

    Lobo, Tasso Julio; Pachon, Carlos Thiene; Pachon, Jose Carlos; Pachon, Enrique Indalecio; Pachon, Maria Zelia; Pachon, Juan Carlos; Santillana, Tomas Guillermo; Zerpa, Juan Carlos; Albornoz, Remy Nelson; Jatene, Adib Domingos

    2015-01-01

    Background Heart failure and atrial fibrillation (AF) often coexist in a deleterious cycle. Objective To evaluate the clinical and echocardiographic outcomes of patients with ventricular systolic dysfunction and AF treated with radiofrequency (RF) ablation. Methods Patients with ventricular systolic dysfunction [ejection fraction (EF) <50%] and AF refractory to drug therapy underwent stepwise RF ablation in the same session with pulmonary vein isolation, ablation of AF nests and of residual atrial tachycardia, named "background tachycardia". Clinical (NYHA functional class) and echocardiographic (EF, left atrial diameter) data were compared (McNemar test and t test) before and after ablation. Results 31 patients (6 women, 25 men), aged 37 to 77 years (mean, 59.8±10.6), underwent RF ablation. The etiology was mainly idiopathic (19 p, 61%). During a mean follow-up of 20.3±17 months, 24 patients (77%) were in sinus rhythm, 11 (35%) being on amiodarone. Eight patients (26%) underwent more than one procedure (6 underwent 2 procedures, and 2 underwent 3 procedures). Significant NYHA functional class improvement was observed (pre-ablation: 2.23±0.56; postablation: 1.13±0.35; p<0.0001). The echocardiographic outcome also showed significant ventricular function improvement (EF pre: 44.68%±6.02%, post: 59%±13.2%, p=0.0005) and a significant left atrial diameter reduction (pre: 46.61±7.3 mm; post: 43.59±6.6 mm; p=0.026). No major complications occurred. Conclusion Our findings suggest that AF ablation in patients with ventricular systolic dysfunction is a safe and highly effective procedure. Arrhythmia control has a great impact on ventricular function recovery and functional class improvement. PMID:25387404

  11. Amiodarone-Induced Third Degree Atrioventricular Block and Extreme QT Prolongation Generating Torsade Des Pointes in Paroxysmal Atrial Fibrillation.

    Science.gov (United States)

    Sequeira, Orlando Robert; Aquino, Nelson Javier; Gómez, Nancy Beatriz; García, Laura Beatriz; Cáceres, Cristina; Lovera, Oscar A; Centurión, Osmar Antonio

    2016-01-01

    Amiodarone is still the most potent antiarrhythmic drug in the prevention of life threatening ventricular arrhythmias and demonstrates a very low incidence of torsade de pointes. An unusual case of an 81-year-old woman who developed serious abnormalities of the conduction system of the heart and torsade des pointes during intravenous infusion of amiodarone for the treatment of paroxysmal atrial fibrillation is described. To the best of our knowledge, this is the first case showing an association of intravenous amiodarone-induced third degree atrioventricular block and extreme QT interval prolongation generating torsade des pointes in a patient with paroxysmal atrial fibrillation who required an implantable cardioverter-defibrillator. Currently, amiodarone is still one of the few remaining treatment options for the medical therapeutic management of serious ventricular arrhythmias and to reduce the incidence of atrial fibrillation without increasing mortality or sudden cardiac death rates in heart failure patients like our elderly present patient. Nevertheless, we have to keep in mind that intravenous amiodarone may generate serious abnormalities of the conduction system of the heart and lethal ventricular arrhythmias in certain patients.

  12. Occlusion of left atrial appendage in patients with atrial fibrillation

    Directory of Open Access Journals (Sweden)

    О. Н. Ганеева

    2015-10-01

    Full Text Available The article reviews a new method of prophylaxis of thromboembolitic complications, specifically occlusion of left atrial appendage, in patients with atrial fibrillation. Indications and contraindications for the procedure, as well as a step-by-step process of the intervention itself are described. Special emphasis is placed on the up-to-date evidence and the review of clinical trials.

  13. Contact force sensing for ablation of persistent atrial fibrillation: A randomized, multicenter trial.

    Science.gov (United States)

    Conti, Sergio; Weerasooriya, Rukshen; Novak, Paul; Champagne, Jean; Lim, Hong Euy; Macle, Laurent; Khaykin, Yaariv; Pantano, Alfredo; Verma, Atul

    2018-02-01

    Impact of contact force sensing (CFS) on ablation of persistent atrial fibrillation (PeAF) is unknown. The purpose of the TOUCH AF (Therapeutic Outcomes Using Contact force Handling during Ablation of Persistent Atrial Fibrillation) randomized trial was to compare CFS-guided ablation to a CFS-blinded strategy. Patients (n = 128) undergoing first-time ablation for persistent AF were randomized to a CFS-guided vs CFS-blinded strategy. In the CFS-guided procedure, operators visualized real-time force data. In the blinded procedure, force data were hidden. Wide antral pulmonary vein isolation plus a roof line were performed. Patients were followed at 3, 6, 9, and 12 months with clinical visit, ECG, and 48-hour Holter monitoring. The primary endpoint was cumulative radiofrequency (RF) time for all procedures. Atrial arrhythmia >30 seconds after 3 months was a recurrence. PeAF was continuous for 26 weeks (interquartile range [IQR] 13-52), and left atrial size was 45 ± 5 mm. Force in the CFS-blinded and CFS-guided arms was 12 g [IQR 6-20] and 14 g [IQR 9-20] (P = .10), respectively. Total RF time did not differ between CFS-guided and CFS-blinded groups (49 ± 14 min vs 50 ± 20 min, respectively; P = .70). Single procedure freedom from atrial arrhythmia was 60% in the CFS-guided arm and 63% in the CFS-blinded arm off drugs. Lesions with gaps were associated with significantly less force (11.4 g [IQR 6-19] vs 13.2 g [IQR 8-20], respectively; P = .0007) and less force-time integral (174 gs [IQR 91-330] vs 210 gs [IQR 113-388], respectively; P force/force-time integral was associated with significantly more gaps. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  14. Selective targeting of gain-of-function KCNQ1 mutations predisposing to atrial fibrillation.

    Science.gov (United States)

    Campbell, Courtney M; Campbell, Jonathan D; Thompson, Christopher H; Galimberti, Eleonora Savio; Darbar, Dawood; Vanoye, Carlos G; George, Alfred L

    2013-10-01

    Atrial fibrillation is the most common sustained cardiac arrhythmia in adults. We hypothesized that gain-of-function KCNQ1 mutations previously associated with familial atrial fibrillation have distinct pharmacological properties that may enable targeted inhibition. Wild-type (WT) KCNQ1 or the familial atrial fibrillation mutation KCNQ1-S140G was heterologously coexpressed with KCNE1 to enable electrophysiological recording of the slow delayed rectifier current (IKs) and investigation of pharmacological effects of the IKs selective blocker HMR-1556. Coexpression of KCNQ1-S140G with KCNE1 generated potassium currents (S140G-IKs) that exhibited greater sensitivity to HMR-1556 than WT-IKs. Enhanced HMR-1556 sensitivity was also observed for another gain-of-function atrial fibrillation mutation, KCNQ1-V141M. Heteromeric expression of KCNE1 with both KCNQ1-WT and KCNQ1-S140G generated currents (HET-IKs) with gain-of-function features, including larger amplitude, a constitutively active component, hyperpolarized voltage dependence of activation, and extremely slow deactivation. A low concentration of HMR-1556, which had little effect on WT-IKs but was capable of inhibiting the mutant channel, reduced both instantaneous and steady state HET-IKs to levels that were not significantly different from WT-IKs and attenuated use-dependent accumulation of the current. In cultured adult rabbit left atrial myocytes, expression of S140G-IKs shortened action potential duration compared with WT-IKs. Application of HMR-1556 mitigated S140G-IKs-induced action potential duration shortening and did not alter action potential duration in cells expressing WT-IKs. The enhanced sensitivity of KCNQ1 gain-of-function mutations for HMR-1556 suggests the possibility of selective therapeutic targeting, and, therefore, our data illustrate a potential proof of principle for genotype-specific treatment of this heritable arrhythmia.

  15. Clinical impact of genetic studies in lethal inherited cardiac arrhythmias.

    Science.gov (United States)

    Shimizu, Wataru

    2008-12-01

    Over the past decade, molecular genetic studies have established a link between a number of inherited cardiac arrhythmias, including congenital long QT syndrome (LQTS) and Brugada syndrome (BrS), and mutations in genes encoding for ion channels or other membrane components. Twelve forms of LQTS have been identified in 50-70% of clinically affected patients. Genotype-phenotype correlations have been rigorously investigated in LQT1, LQT2 and LQT3 syndromes, which constitute more than 90% of genotyped LQTS patients, enabling stratification of risk and effective treatment of genotyped patients. Genotype-specific triggers for both the cardiac events and the clinical course have been reported, and genotype-specific therapy has been already introduced. More recently, mutation site-specific differences in the clinical phenotype have been reported in LQT1 and LQT2 patients, indicating the possibility of mutation site-specific management or treatment. In contrast, only one-third of BrS patients can be genotyped, and data on genotype-phenotype relationships in clinical studies are limited. A Haplotype B consisting of 6 individual DNA polymorphisms within the proximal promoter region of the SCN5A gene was recently identified only in Asians (frequency 22%). Individuals with Haplotype B show significantly longer duration of both PQ and QRS than those without Haplotype B, indicating that Haplotype B likely contributes to the higher incidence of BrS in Asian populations.

  16. Treatment of atrial fibrillation with a dual defibrillator in heart failure patients (TRADE HF: protocol for a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Grandinetti Giuseppe

    2011-02-01

    Full Text Available Abstract Background Heart failure(HF and atrial fibrillation(AF frequently coexist in the same patient and are associated with increased mortality and frequent hospitalizations. As the concomitance of AF and HF is often associated with a poor prognosis, the prompt treatment of AF in HF patients may significantly improve outcome. Methods/design Recent implantable cardiac resynchronization (CRT devices allow electrical therapies to treat AF automatically. TRADE-HF (trial registration: NCT00345592; http://www.clinicaltrials.gov is a prospective, randomized, double arm study aimed at demonstrating the efficacy of an automatic, device-based therapy for treatment of atrial tachycardia and fibrillation(AT/AF in patients indicated for CRT. The study compares automatic electrical therapy to a traditional more usual treatment of AT/AF: the goal is to demonstrate a reduction in a combined endpoint of unplanned hospitalizations for cardiac reasons, death from cardiovascular causes or permanent AF when using automatic atrial therapy as compared to the traditional approach involving hospitalization for symptoms and in-hospital treatment of AT/AF. Discussion CRT pacemaker with the additional ability to convert AF as well as ventricular arrhythmias may play a simultaneous role in rhythm control and HF treatment. The value of the systematic implantation of CRT ICDs with the capacity to deliver atrial therapy in HF patients at risk of AF has not yet been explored. The TRADE-HF study will assess in CRT patients whether a strategy based on automatic management of atrial arrhythmias might be a valuable option to reduce the number of hospital admission and to reduce the progression the arrhythmia to a permanent form. Trial registration NCT00345592

  17. Long-term Impact of Continuous Positive Airway Pressure Therapy on Arrhythmia and Heart Rate Variability in Patients With Sleep Apnea.

    Science.gov (United States)

    Grau, Nuria; Bazan, Victor; Kallouchi, Mohamed; Rodriguez, Diego; Estirado, Cristina; Corral, Maria Isabel; Valls, Maria Teresa; Ramos, Pablo; Sanjuas, Carles; Felez, Miquel; Valles, Ermengol; Benito, Begoña; Gea, Joaquim; Bruguera-Cortada, Jordi; Martí-Almor, Julio

    2016-01-01

    Autonomic dysfunction can alter heart rate variability and increase the incidence of arrhythmia. We analyzed the impact of continuous positive airway pressure (CPAP) on this pathophysiological phenomenon in patients with severe sleep apnea-hypopnea syndrome. Consecutive patients with recently diagnosed severe sleep apnea-hypopnea syndrome were prospectively considered for inclusion. Incidence of arrhythmia and heart rate variability (recorded on a 24-hour Holter monitoring device) were analyzed before starting CPAP therapy and 1 year thereafter. A total of 26 patients were included in the study. CPAP was administered for 6.6 ± 1.8 hours during Holter monitoring. After starting CPAP, we observed a marginally significant reduction in mean HR (80 ± 9 to 77 ± 11 bpm, p=.05). CPAP was associated with partial modulation (only during waking hours) of r-MSSD (p=.047) and HF (p=.025) parasympathetic parameters and LF (p=.049) sympathetic modulation parameters. None of these parameters returned completely to normal levels (p<.001). The number of unsustained episodes of atrial tachycardia diminished (p=.024), but no clear effect on other arrhythmias was observed. CPAP therapy only partially improves heart rate variability, and exclusively during waking hours, and reduces incidence of atrial tachycardia, both of which can influence cardiovascular morbidity and mortality in sleep apnea-hypopnea syndrome patients. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  18. Nonalcoholic Fatty Liver Disease (NAFLD) and Risk of Cardiac Arrhythmias: A New Aspect of the Liver-heart Axis.

    Science.gov (United States)

    Mantovani, Alessandro

    2017-06-28

    Nonalcoholic fatty liver disease (NAFLD) is a pathologic condition frequently observed in clinical practice. To date, the prevalence of NAFLD is approximately 25-30% among adults of the general population in Western countries but increases to approximately 70-75% among patients with type 2 diabetes mellitus. In the last decade, accumulating evidence has clearly demonstrated that patients with NAFLD have not only an increased liver-related morbidity and mortality but also an increased risk of fatal and non-fatal cardiovascular events. In particular, several studies have documented the existence of an independent association among NAFLD and cardiac changes in structure and function in both non-diabetic and diabetic patients. In addition, mounting evidence also suggests that there is a strong relationship between NAFLD and cardiac arrhythmias, such as atrial fibrillation, QTc prolongation and ventricular arrhythmias. This is of clinical interest, as it could explain, at least in part, the increased risk of death for cardiovascular disease in patients with NAFLD. Therefore, seeing that cardiovascular disease complications are the leading cause of disability and death in NAFLD patients, the recent European clinical practice guidelines advised to check the cardiovascular system in all patients with NAFLD. This clinical mini review will briefly describe the increasing body of evidence regarding the association between NAFLD and cardiac arrhythmias, and discuss the potential biological mechanisms underlying this association.

  19. Complexity Measure Revisited: A New Algorithm for Classifying Cardiac Arrhythmias

    Science.gov (United States)

    2001-10-25

    Complexity Measure Revisited: A New Algorithm for Classifying Cardiac Arrhythmias Contract Number Grant Number Program Element Number Author(s) Project...to set-up the acquisition and processing characteristics of ECG signal. REFERENCES [1] Special Issue on Electrical Therapy of Cardiac Arrhythmias , 3URFHHGLQJV...JM Jenkins, LA DiCarlo. “Detection and Identification of Cardiac Arrhythmias Using an adaptive, Linear-Predictive Filter”, ,((( &RPSXWHUV LQ

  20. Atrial Conduction Slows Immediately Before the Onset of Human Atrial Fibrillation

    Science.gov (United States)

    Lalani, Gautam G.; Schricker, Amir; Gibson, Michael; Rostamian, Armand; Krummen, David E.; Narayan, Sanjiv M.

    2012-01-01

    Objectives The aim of this study was to determine whether onset sites of human atrial fibrillation (AF) exhibit conduction slowing, reduced amplitude, and/or prolonged duration of signals (i.e., fractionation) immediately before AF onset. Background Few studies have identified functional determinants of AF initiation. Because conduction slowing is required for reentry, we hypothesized that AF from pulmonary vein triggers might initiate at sites exhibiting rate-dependent slowing in conduction velocity (CV restitution) or local slowing evidenced by signal fractionation. Methods In 28 patients with AF (left atrial size 43 ± 5 mm; n = 13 persistent) and 3 control subjects (no AF) at electrophysiological study, we measured bi-atrial conduction time (CT) electrogram fractionation at 64 or 128 electrodes with baskets in left (n = 17) or both (n = 14) atria during superior pulmonary vein pacing at cycle lengths (CL) accelerating from 500 ms (120 beats/min) to AF onset. Results Atrial fibrillation initiated in 19 of 28 AF patients and no control subjects. During rate acceleration, conduction slowed in 23 of 28 AF patients (vs. no control subjects, p = 0.01) at the site of AF initiation (15 of 19) or latest activated site (20 of 28). The CT lengthened from 79 ± 23 ms to 107 ± 39 ms (p < 0.001) on acceleration, in a spectrum from persistent AF (greatest slowing) to control subjects (least slowing; p < 0.05). Three patterns of CV restitution were observed: 1) broad (gradual CT prolongation, 37% patients); 2) steep (abrupt prolongation, at CL 266 ± 62 ms, 42%); and 3) flat (no prolongation, 21% AF patients, all control subjects). The AF initiation was more prevalent in patients with CV restitution (17 of 23 vs. 2 of 8; p = 0.03) and immediately followed abrupt reorientation of the activation vector in patients with broad but not steep CV restitution (p < 0.01). Patients with broad CV restitution had larger atria (p = 0.03) and were more likely to have persistent AF (p = 0

  1. SERCA in genesis of arrhythmias: what we already know and what is new?

    Science.gov (United States)

    Erkasap, Nilüfer

    2007-07-01

    This review mainly focuses on the structure, function of the sarco(endo)plasmic reticulum calcium pump (SERCA) and its role in genesis of arrhythmias. SERCA is a membrane protein that belongs to the family of P-type ion translocating ATPases and pumps free cytosolic calcium into intracellular stores. Active transport of Ca2+ is achieved, according to the E1-E2 model, changing of SERCA structure by Ca2+. The affinity of Ca2+ -binding sites varies from high (E1) to low (E2). Three different SERCA genes were identified-SERCA1, SERCA2, and SERCA3. SERCA is mainly represented by the SERCA2a isoform in the heart. In heart muscle, during systole, depolarization triggers the release of Ca2+ from the sarcoplasmic reticulum (SR) and starts contraction. During diastole, muscle relaxation occurs as Ca2+ is again removed from cytosol, predominantly by accumulation into SR via the action of SERCA2a. The main regulator of SERCA2a is phospholamban and another regulator proteolipid of SERCA is sarcolipin. There are a lot of studies on the effect of decreased and/or increased SERCA activity in genesis of arrhythmia. Actually both decrease and increase of SERCA activity in the heart result in some pathological mechanisms such as heart failure and arrhythmia.

  2. Bursting in Cellular Automata and Cardiac Arrhythmias

    Science.gov (United States)

    Bub, Gil; Shrier, Alvin; Glass, Leon

    2013-01-01

    The mechanisms underlying the initiation and continuation of abnormal cardiac arrhythmias are incompletely understood. In this chapter, we summarize work that shows how simple cellular automata models of excitable media can display a range of interesting dynamical behavior including spontaneous bursts of reentrant spiral activity. Since the model incorporates basic physiological properties of excitability, heterogeneity, localized pacemakers, and fatigue in a schematic way, the model captures generic physiological dynamics that should be broadly observed in experimental and clinical settings as well as in more realistic mathematical models.

  3. MicroRNAs in cardiac arrhythmia

    DEFF Research Database (Denmark)

    Hedley, Paula L; Carlsen, Anting L; Christiansen, Kasper M

    2014-01-01

    Long QT syndrome (LQTS) is a genetic cardiac condition associated with prolonged ventricular repolarization, primarily a result of perturbations in cardiac ion channels, which predisposes individuals to life-threatening arrhythmias. Using DNA screening and sequencing methods, over 700 different...... cardiovascular diseases. MiR-1 and MiR-133A are the most abundant miRNAs in the heart and have both been reported to regulate cardiac ion channels. We hypothesized that, as a consequence of their role in regulating cardiac ion channels, genetic variation in the genes which encode MiR-1 and MiR-133A might explain...

  4. Basic Cardiac Electrophysiology and Common Drug-induced Arrhythmias.

    Science.gov (United States)

    Lee, Aimee; Pickham, David

    2016-09-01

    Drugs can be a double-edged sword, providing the benefit of symptom alleviation and disease modification but potentially causing harm from adverse cardiac arrhythmic events. Proarrhythmia is the ability of a drug to cause an arrhythmia, the number one reason for drugs to be withdrawn from the patient. Drug-induced arrhythmias are defined as the production of de novo arrhythmias or aggravation of existing arrhythmias, as a result of previous or concomitant pharmacologic treatment. This review summarizes normal cardiac cell and tissue functioning and provides an overview of drugs that effect cardiac repolarization and the adverse effects of commonly administered antiarrhythmics. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Malignant Arrhythmia in Apical Ballooning Syndrome: Risk Factors and Outcomes

    Directory of Open Access Journals (Sweden)

    Samuel J. Asirvatham

    2008-08-01

    Full Text Available Objectives: We sought to determine the frequency and outcomes with symptomatic arrhythmia in patients with apical ballooning syndrome (ABS. Methods: A retrospective review of the Mayo Clinic Angiography database was conducted to identify patients who met the Mayo criteria for ABS. Patients with documented arrhythmias formed the study group, and 31 randomly selected patients with ABS but without arrhythmia formed the control group.Results: Out of 105 patients identified with ABS, 6 (5.7% women aged 69 +/- 9 years experienced significant arrhythmia (ventricular fibrillation, asystole, 2 patients died, and 1 required permanent pacemaker implantation. When compared with controls, the study group showed no significant difference with respect to ECG characteristics (QT, QRS duration or axis except for R-R interval variability (see comments below (30.6±6 vs 14.5±17 p = 0.0004, QTc, and P-R interval. Patients without arrhythmia were more likely to be on beta-blocker therapy than the study population (33% vs 80.6% p = 0.02. Conclusion: Life-threatening arrhythmia is uncommon (5.7% with ABS despite marked, structural abnormalities. When arrhythmias do occur, the outcome is poor. Prominent variability in R-R intervals appears to be predictive of significant arrhythmias in ABS. The role of beta-blocker therapy in preventing arrhythmia with ABS requires further investigation.

  6. Dispersion of P wave duration and P wave vector in patients with atrial septal aneurysm.

    Science.gov (United States)

    Janion, Marianna; Kurzawski, Jacek; Sielski, Janusz; Ciuraszkiewicz, Katarzyna; Sadowski, Marcin; Radomska, Edyta

    2007-07-01

    Atrial septal aneurysm (ASA) may be involved in the genesis of atrial arrhythmias as a consequence of disturbances in the propagation of depolarization, which may be easily assessed by P wave dispersion measurement. The aim of this study is to assess the dispersion of P wave duration and P wave vector in patients with ASA and to determine the effect of associated interatrial shunt on the magnitude of P wave dispersion. The study population consisted of 23 healthy volunteers and 88 patients with ASA base more than 15 mm and protrusion more than 7.5 mm. The size of aneurysms and atria was determined by echocardiography and P wave dispersion was measured on the surface ECG. In ASA patients, dispersion of P wave duration was significantly increased when compared with healthy controls (7.8 +/- 12.1 vs. 3.7 +/- 3.5 ms; P wave vector was also significantly increased (8.5 +/- 10.1 degrees vs. 4.6 +/- 3.6 degrees ; P wave duration and P wave vector. Variation in P wave duration was significantly correlated with the dispersion of P wave vector and age of these patients. Dispersion of P wave vector was significantly decreased in ASA patients with interatrial shunt. P wave dispersion in ASA patients may predispose to the development of atrial arrhythmias.

  7. Novel anti-arrhythmic medications in the treatment of atrial fibrillation.

    Science.gov (United States)

    Saklani, Pradyot; Skanes, Allan

    2012-11-01

    Atrial fibrillation (AF) is a prevalent condition particularly amongst the elderly, which contributes to both morbidity and mortality. The burden of disease has lead to significant increases in health care utilization and cost in recent years. Treatment of Atrial fibrillation consists of either a rate or rhythm control strategy. Rhythm control is achieved using medical management and/or catheter ablation. In spite of major strides in catheter ablation, this procedure remains a second line treatment of AF. Anti-arrhythmic medications represent the main treatment modality for the maintenance of sinus rhythm. Amiodarone has been used for decades because of its efficacy and lack of pro-arrhythmia despite numerous extracardiac side effects. Novel agents such as Dronedarone were designed to emulate Amiodarone without the extra-cardiac side effects. Unfortunately recent trials have raised concerns for the safety of this medication in certain patients. Other agents such as Vernakalant and Ranolazine are in development that promise to be more atrial selective in their action, thereby potentially avoiding pro-arrhythmia and heart failure side effects. It remains to be seen however if one or more of these agents achieves the required high efficacy and safety threshold. This review summarizes the main anti-arrhythmic clinical trials, early phase trials involving novel agents and examines the conflicting data relating to Dronedarone.

  8. Atrial fibrillation does not affect ankle-brachial index measured using the Doppler method.

    Science.gov (United States)

    Dąbrowski, Michał; Lewandowski, Jacek; Abramczyk, Piotr; Łoń, Izabela; Gaciong, Zbigniew; Siński, Maciej

    2017-11-02

    Atrial fibrillation may affect blood pressure measurements. The ankle-brachial index (ABI) is a ratio of systolic blood pressure measured on the lower and upper limbs that may also be affected by arrhythmia. The purpose of the study was to investigate whether atrial fibrillation influenced ABI results. Ninety-nine patients (age 66.6±11 years, 63 males and 36 females) who underwent electrical cardioversion of atrial fibrillation were investigated. ABI measurements using the Doppler method were performed on both lower extremities before and after electrical cardioversion. Measurements were repeated three times and then averaged. The ABI using both lower limbs was lower before electrical cardioversion than after restoration to sinus rhythm (right side: 1.132 (1.065-1.210) during atrial fibrillation vs. 1.179 (1.080-1.242) in sinus rhythm, P=0.019; left side: 1.142 (1.075-1.222) during atrial fibrillation vs. 1.170 (1.098-1.255) in sinus rhythm, P=0.011). However, the upper 95% confidence interval (CI) margins for the median differences in ABI were 0.045 and 0.040 for right and left, respectively, suggesting that the observed difference was clinically insignificant. There was a significant correlation between measurements obtained before and after electrical cardioversion on both lower limbs (r=0.61, P<0.001 and r=0.67, P<0.001). The Bland-Altman plot showed good agreement between measurements performed using the Doppler method during atrial fibrillation and sinus rhythm. Study results showed that atrial fibrillation did not have a clinically important effect on ABI measurements.Hypertension Research advance online publication, 2 November 2017; doi:10.1038/hr.2017.89.

  9. Long working hours as a risk factor for atrial fibrillation: a multi-cohort study.

    Science.gov (United States)

    Kivimäki, Mika; Nyberg, Solja T; Batty, G David; Kawachi, Ichiro; Jokela, Markus; Alfredsson, Lars; Bjorner, Jakob B; Borritz, Marianne; Burr, Hermann; Dragano, Nico; Fransson, Eleonor I; Heikkilä, Katriina; Knutsson, Anders; Koskenvuo, Markku; Kumari, Meena; Madsen, Ida E H; Nielsen, Martin L; Nordin, Maria; Oksanen, Tuula; Pejtersen, Jan H; Pentti, Jaana; Rugulies, Reiner; Salo, Paula; Shipley, Martin J; Suominen, Sakari; Theorell, Töres; Vahtera, Jussi; Westerholm, Peter; Westerlund, Hugo; Steptoe, Andrew; Singh-Manoux, Archana; Hamer, Mark; Ferrie, Jane E; Virtanen, Marianna; Tabak, Adam G

    2017-09-07

    Studies suggest that people who work long hours are at increased risk of stroke, but the association of long working hours with atrial fibrillation, the most common cardiac arrhythmia and a risk factor for stroke, is unknown. We examined the risk of atrial fibrillation in individuals working long hours (≥55 per week) and those working standard 35-40 h/week. In this prospective multi-cohort study from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium, the study population was 85 494 working men and women (mean age 43.4 years) with no recorded atrial fibrillation. Working hours were assessed at study baseline (1991-2004). Mean follow-up for incident atrial fibrillation was 10 years and cases were defined using data on electrocardiograms, hospital records, drug reimbursement registers, and death certificates. We identified 1061 new cases of atrial fibrillation (10-year cumulative incidence 12.4 per 1000). After adjustment for age, sex and socioeconomic status, individuals working long hours had a 1.4-fold increased risk of atrial fibrillation compared with those working standard hours (hazard ratio = 1.42, 95% CI = 1.13-1.80, P = 0.003). There was no significant heterogeneity between the cohort-specific effect estimates (I2 = 0%, P = 0.66) and the finding remained after excluding participants with coronary heart disease or stroke at baseline or during the follow-up (N = 2006, hazard ratio = 1.36, 95% CI = 1.05-1.76, P = 0.0180). Adjustment for potential confounding factors, such as obesity, risky alcohol use and high blood pressure, had little impact on this association. Individuals who worked long hours were more likely to develop atrial fibrillation than those working standard hours.

  10. Safety and efficacy of vernakalant for acute cardioversion of atrial fibrillation: an update

    Directory of Open Access Journals (Sweden)

    Dobrev D

    2013-04-01

    Full Text Available Yukiomi Tsuji,1 Dobromir Dobrev1–3 1Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, 2Division of Experimental Cardiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, 3Deutsches Zentrum für Herz-Kreislauf-Forshcung [German Center for Cardiovascular Research], partner site Heidelberg/Mannheim, Mannheim, Germany Abstract: Intravenous vernakalant has recently been approved in Europe as an atrial-selective antiarrhythmic drug for the conversion of recent-onset atrial fibrillation (AF. It inhibits atrial-selective K+ currents (IK,ACh and IKur and causes rate-dependent atrial-predominant Na+ channel block, with only a small inhibitory effect on the rapid delayed rectifier K+ current (IKr in the ventricle. Due to its atrial-selective properties, vernakalant prolongs the effective refractory period of the atria with minimal effects on the ventricles, being associated with a low proarrhythmic risk for torsades de pointes arrhythmias. Five pivotal clinical trials consistently demonstrated that vernakalant rapidly terminates AF with stable maintenance of sinus rhythm for up to 24 hours. A head-to-head comparative trial showed that the 90-minute conversion rate of vernakalant was substantially higher than that of amiodarone. Initially, a longer-acting oral formulation of vernakalant was shown to be effective and safe in preventing AF recurrence after cardioversion in a Phase IIb study. However, the clinical studies testing oral vernakalant for maintenance of sinus rhythm after AF cardioversion were prematurely halted for undisclosed reasons. This review article provides an update on the safety and efficacy of intravenous vernakalant for the rapid cardioversion of AF. Keywords: atrial fibrillation, antiarrhythmic drug, atrial-selective K+ currents, Na+ channel block, ventricles

  11. Burden of disease and cost of illness of atrial fibrillation in Portugal.

    Science.gov (United States)

    Gouveia, Miguel; Costa, João; Alarcão, Joana; Augusto, Margarida; Caldeira, Daniel; Pinheiro, Luís; Vaz Carneiro, António; Borges, Margarida

    2015-01-01

    Atrial fibrillation is the most prevalent sustained arrhythmia. This paper estimates the burden and cost of illness attributable to atrial fibrillation in Portugal based on demographic and health statistics. Mortality data by cause of death came from the European Detailed Mortality Database of the World Health Organization (WHO). Hospital data were taken from the Portuguese diagnosis-related groups database. The burden of disease was measured using DALYs (disability-adjusted life years), a metric adopted by the WHO. Costs studied included resource use and lost productivity. The burden and cost of illness are those attributable to atrial fibrillation and its main complication, ischemic stroke. In Portugal, 4070 deaths were attributable to atrial fibrillation in 2010, corresponding to 3.8% of all deaths. In total, the burden of disease attributable to atrial fibrillation was estimated at 23,084 DALYs: 10,521 resulting from premature deaths (1.7% of the total DALYs due to death in 2010 in Portugal), and 12,563 resulting from disability. The total estimated direct costs attributable to atrial fibrillation at 2013 prices were €115 million: €34 million for inpatient care and €81 million for outpatient care. Indirect costs resulting from lost production due to disability were estimated at €25 million. Atrial fibrillation has an important social impact in Portugal due to its associated mortality and morbidity, and was responsible in 2013 for a total cost of €140 million, about 0.08% of gross domestic product. Copyright © 2014. Published by Elsevier España.

  12. Atrial fibrillation: inflammation in disguise?

    NARCIS (Netherlands)

    Lappegard, K.T.; Hovland, A.; Pop, G.A.M.; Mollnes, T.E.

    2013-01-01

    Atrial fibrillation is highly prevalent, and affected patients are at an increased risk of a number of complications, including heart failure and thrombo-embolism. Over the past years, there has been increasing interest in the role of inflammatory processes in atrial fibrillation, from the first

  13. Incidence of postoperative atrial fibrillation in patients undergoing on-pump and off-pump coronary artery bypass grafting

    Science.gov (United States)

    Bohatch Júnior, Milton Sérgio; Matkovski, Paula Dayana; Giovanni, Frederico José Di; Fenili, Romero; Varella, Everton Luz; Dietrich, Anderson

    2015-01-01

    Objective To determine the incidence of postoperative atrial fibrillation in patients undergoing on-pump and off-pump coronary artery bypass grafting. Methods A retrospective study with analysis of 230 medical records between January 2011 and October 2013 was conducted. Results Fifty-six (24.3%) out of the 230 patients were female. The average age of patients undergoing on-pump coronary artery bypass grafting was 59.91±8.62 years old, and off-pump was 57.16±9.01 years old (P=0.0213). The average EuroSCORE for the on-pump group was 3.37%±3.08% and for the off-pump group was 3.13%±3% (P=0.5468). Eighteen (13.43%) patients who underwent off-pump coronary artery bypass grafting developed postoperative atrial fibrillation, whereas for the onpump group, 19 (19.79%) developed this arrhythmia, with no significant difference between the groups (P=0.1955). Conclusion Off-pump coronary artery bypass grafting did not reduce the incidence of atrial fibrillation in the postoperative period. Important predictors of risk for the development of this arrhythmia were identified as: patients older than 70 years old and presence of atrial fibrillation in perioperative period in both groups, and non-use of beta-blockers drugs postoperatively in the on-pump group. PMID:26313722

  14. High-fat diet-dependent modulation of the delayed rectifier K(+) current in adult guinea pig atrial myocytes.

    Science.gov (United States)

    Aromolaran, Ademuyiwa S; Colecraft, Henry M; Boutjdir, Mohamed

    2016-06-03

    Obesity is associated with hyperlipidemia, electrical remodeling of the heart, and increased risk of supraventricular arrhythmias in both male and female patients. The delayed rectifier K(+) current (IK), is an important regulator of atrial repolarization. There is a paucity of studies on the functional role of IK in response to obesity. Here, we assessed the obesity-mediated functional modulation of IK in low-fat diet (LFD), and high-fat diet (HFD) fed adult guinea pigs. Guinea pigs were randomly divided into control and obese groups fed, ad libitum, with a LFD (10 kcal% fat) or a HFD (45 kcal% fat) respectively. Action potential duration (APD), and IK were studied in atrial myocytes and IKr and IKs in HEK293 cells using whole-cell patch clamp electrophysiology. HFD guinea pigs displayed a significant increase in body weight, total cholesterol and total triglycerides within 50 days. Atrial APD at 30% (APD30) and 90% (APD90) repolarization were shorter, while atrial IK density was significantly increased in HFD guinea pigs. Exposure to palmitic acid (PA) increased heterologously expressed IKr and IKs densities, while oleic acid (OA), severely reduced IKr and had no effect on IKs. The data are first to show that in obese guinea pigs abbreviated APD is due to increased IK density likely through elevations of PA. Our findings may have crucial implications for targeted treatment options for obesity-related arrhythmias. Published by Elsevier Inc.

  15. Fluoroscopy integrated 3D mapping significantly reduces radiation exposure during ablation for a wide spectrum of cardiac arrhythmias.

    Science.gov (United States)

    Christoph, Marian; Wunderlich, Carsten; Moebius, Stefanie; Forkmann, Mathias; Sitzy, Judith; Salmas, Jozef; Mayer, Julia; Huo, Yan; Piorkowski, Christopher; Gaspar, Thomas

    2015-06-01

    Despite the use of established 3D-mapping systems, invasive electrophysiological studies and catheter ablation require high radiation exposure of patients and medical staff. This study investigated whether electroanatomic catheter tracking in prerecorded X-ray images on top of an existing 3D-mapping system has any impact on radiation exposure. Two hundred and ninety-five consecutive patients were either ablated with the guidance of the traditional CARTO-3 system (c3) or with help of the CARTO-UNIVU system (cU): [typical atrial flutter (AFL) n = 58, drug refractory atrial fibrillation (AF) n = 81, ectopic atrial tachycardia (EAT) n = 37, accessory pathways (APs) n = 22, symptomatic, idiopathic premature ventricular complexes (PVCs) n = 56, ventricular tachycardias (VTs) n = 41]. The CARTO-UNIVU allowed a reduction in radiation exposure: fluoroscopy time: AFL c3: 8.6 ± 0.8 min vs. cU: 2.9 ± 0.3 min, P cardiac arrhythmias, and especially in AF and VT ablation, fluoroscopy integrated 3D mapping contributed to a dramatic reduction in radiation exposure without prolonging procedure times and compromising patient's safety. That effect, however, could not be maintained in patients with APs and PVCs. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  16. Arrhythmia risk assessment using heart rate variability parameters in patients with frequent ventricular ectopic beats without structural heart disease.

    Science.gov (United States)

    Barutçu, Ahmet; Temiz, Ahmet; Bekler, Adem; Altun, Burak; Kirilmaz, Bahadir; Aksu, Feyza Ulusoy; Küçük, Uğur; Gazi, Emine

    2014-11-01

    Ventricular ectopic beats (VEBs) are usually considered a benign condition that can be managed with conservative measures. Heart rate variability (HRV), which is one of the most important methods for assessing autonomic activity, is a noninvasive, quantitative method of analyzing autonomic effects on the heart. We aimed to investigate the risk of arrhythmia in patients with VEBs and without cardiovascular disease by using HRV parameters. Patients with frequent VEBs (more than 30 times in 1 hour, according to the Lown classification) were identified. Identified patients were evaluated by 24-hour ECG recording. Our study included 43 patients with frequent VEBs and 43 controls. General characteristics of the study population were similar. The LF (low frequency)/HF (high frequency) ratio was significantly higher in the frequent VEBs group than in the control group (P < 0.001). The rate of paroxysmal atrial fibrillation (PAF) was higher in the frequent VEB group than in the control group (P = 0.003). The number of VEBs was correlated with LF/HF ratio and PAF (r = 0.339, P = 0.001 and r = 0.294, P = 0.006, respectively). Our study showed that the sympathetic nervous system is dominant in young patients with VEBs and without significant comorbidities. There is a higher risk of atrial fibrillation in patients with VEBs and they should be monitored closely for atrial fibrillation. ©2014 Wiley Periodicals, Inc.

  17. Cancer chemotherapy and cardiac arrhythmias: a review.

    Science.gov (United States)

    Tamargo, Juan; Caballero, Ricardo; Delpón, Eva

    2015-02-01

    Cardiovascular toxicity is a potential complication of cancer chemotherapy (CC) that increases the morbidity and mortality of cancer patients. Cardiac arrhythmias have been reported as an adverse effect of many chemotherapeutic drugs, including novel targeted therapies. The relationship between chemotherapy and arrhythmias has not been well-established and the proarrhythmogenic mechanisms remain uncertain as they can be the result of a direct electrophysiological effect or of changes in cardiac structure and function, including myocardial ischaemia and heart failure, which create an arrhythmogenic substrate. In this review we summarise available evidence of proarrhythmia induced by CC, discuss the possible mechanisms involved in this adverse effect and emphasise the importance of cardiac monitoring for the early diagnosis, intervention and surveillance of those patients more susceptible to develop proarrhythmia in an attempt to reduce the morbidity and mortality. Oncologists should be fully aware of proarrhythmia and the close collaboration between cardiologists and oncologists would result in a better cardiovascular assessment, risk stratification, cardiac monitoring and treatment during CC and during the follow-up. The final objective is to understand the mechanisms of proarrhythmia and evaluate its real incidence and clinical relevance so as to select the safest and most effective treatment for cancer patients.

  18. Arrhythmias and sudden death in heart failure.

    Science.gov (United States)

    Stevenson, W G; Sweeney, M O

    1997-09-01

    Survival of patients with heart failure has improved over the past decade due to advances in medical therapy. Sudden death continues to cause 20 to 50% of deaths. Ventricular arrhythmias are common in patients with heart failure. Ventricular hypertrophy, scars from prior myocardial infarction, sympathetic activation, and electrolyte abnormalities contribute. Some sudden deaths are due to bradyarrhythmias and electromechanical dissociation rather than ventricular arrhythmias. The risks and benefits of antiarrhythmic therapies continue to be defined. Class I antiarrhythmic drugs should be avoided due to proarrhythmic and negative inotropic effects that may increase mortality. For patients resuscitated from sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) amiodarone or an implantable cardioverter defibrillator (ICD) should be considered. ICDs markedly reduce sudden death in VT/VF survivors, but in advanced heart failure, this may not markedly extend survival. Catheter or surgical ablation can be considered for selected patients with bundle branch reentry VT or difficult to control monomorphic VT. For patients who have not had sustained VT/VF antiarrhythmic therapy should generally be avoided, but may benefit some high risk patients. Amiodarone may be beneficial in patients with advanced heart failure and rapid resting heart rates. ICDs may improve survival in selected survivors of myocardial infarction who have inducible VT.

  19. Loperamide Induced Life Threatening Ventricular Arrhythmia

    Directory of Open Access Journals (Sweden)

    Ankit Upadhyay

    2016-01-01

    Full Text Available Loperamide is over-the-counter antidiarrheal agent acting on peripherally located μ opioid receptors. It is gaining popularity among drug abusers as opioid substitute. We report a case of a 46-year-old male that was presented after cardiac arrest. After ruling out ischemia, cardiomyopathy, pulmonary embolism, central nervous system pathology, sepsis, and other drug toxicity, we found out that patient was using around 100 mg of Loperamide to control his chronic diarrhea presumably because of irritable bowel syndrome for last five years and consumed up to 200 mg of Loperamide daily for last two days before the cardiac arrest. We hypothesize that the patient’s QTc prolongation and subsequent cardiac arrest are due to Loperamide toxicity. Patient experienced gradual resolution of tachyarrhythmia and gradual decrease in QTc interval during hospitalization which supports the evidence of causal relationship between Loperamide overdose and potentially fatal arrhythmias. It also provided the clue that patient may have congenital long QT syndrome which was unmasked by Loperamide causing ventricular arrhythmias. This case adds one more pearl in the literature to support that Loperamide overdose related cardiac toxicity does exist and it raises concerns over Loperamide abuse in the community.

  20. Genetics of inherited primary arrhythmia disorders

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    Spears DA

    2015-09-01

    Full Text Available Danna A Spears, Michael H Gollob Division of Cardiology – Electrophysiology, University Health Network, Toronto General Hospital, Toronto, ON, Canada Abstract: A sudden unexplained death is felt to be due to a primary arrhythmic disorder when no structural heart disease is found on autopsy, and there is no preceding documentation of heart disease. In these cases, death is presumed to be secondary to a lethal and potentially heritable abnormality of cardiac ion channel function. These channelopathies include congenital long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome, and short QT syndrome. In certain cases, genetic testing may have an important role in supporting a diagnosis of a primary arrhythmia disorder, and can also provide prognostic information, but by far the greatest strength of genetic testing lies in the screening of family members, who may be at risk. The purpose of this review is to describe the basic genetic and molecular pathophysiology of the primary inherited arrhythmia disorders, and to outline a rational approach to genetic testing, management, and family screening. Keywords: long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome, short QT syndrome, genetics

  1. Prevalence of atrial fibrillation in Asia and the world

    Directory of Open Access Journals (Sweden)

    Eitaro Kodani

    2012-12-01

    Full Text Available Atrial fibrillation (AF is the most common arrhythmia in persons of advanced age, and it is a potent risk factor for cardiogenic ischemic stroke. The overall prevalence of AF is less than 1%, but in people aged 80 years or older the rate is approximately 7–14% in Western countries and 2–3% in Japan. The number of people with AF has been increasing worldwide as the population has aged, and continued increases in the prevalence and incidence of AF are expected with the aging of society. It is predicted that 5–16 million in the United States and more than 1 million in Japan will be affected by 2050. Therefore, AF is one of important diseases that needs to be managed because it is a common disease in aged populations.

  2. Sudden death in a young patient with atrial fibrillation

    Directory of Open Access Journals (Sweden)

    María Tamargo

    2017-08-01

    Full Text Available Sudden cardiac death (SCD in young patients without structural heart disease is frequently due to inherited channelopathies such as long QT syndrome (LQTS, Brugada syndrome or Catecholaminergic polymorphic ventricular tachycardia. Accordingly, the addition of genetic testing to clinical data may be useful to identify the cause of the sudden death in this population. Mutations in the KCNQ1 encoded Kv7.1 channel are related to type 1 LQTS, familial atrial fibrillation (AF, short QT syndrome, and SCD. We present a clinical case where the presence of AF after resuscitation in a young man with cardiac arrest was the key clinical data to suspect an inherited disorder and genetic testing was the main determinant for identifying the cause of the cardiac arrest. The KCNQ1 p.Arg231His mutation explained the combined phenotype of AF and susceptibility to ventricular arrhythmias. The case highlights the importance of continued research in genetics and molecular mechanisms of channelopathies.

  3. A Simple Model for Identifying Critical Structures in Atrial Fibrillation

    CERN Document Server

    Christensen, Kim; Peters, Nicholas S

    2014-01-01

    Atrial fibrillation (AF) is the most common abnormal heart rhythm and the single biggest cause of stroke. Ablation, destroying regions of the atria, is applied largely empirically and can be curative but with a disappointing clinical success rate. We design a simple model of activation wavefront propagation on a structure mimicking the branching network architecture of heart muscle and show how AF emerges spontaneously as age-related parameters change. We identify regions responsible for the initiation and maintenance of AF, the ablation of which terminates AF. The simplicity of the model allows us to calculate analytically the risk of arrhythmia. This analytical result allows us to locate the transition in parameter space and highlights that the transition from regular to fibrillatory behaviour is a finite-size effect present in systems of any size. These clinically testable predictions might inform ablation therapies and arrhythmic risk assessment.

  4. Role of spiral wave pinning in inhomogeneous active media in the termination of atrial fibrillation by electrical cardioversion.

    Science.gov (United States)

    Kuklik, Pawel; Wong, Christopher X; Brooks, Anthony G; Zebrowski, Jan Jacek; Sanders, Prashanthan

    2010-03-01

    Atrial fibrillation is the most common type of arrhythmia to affect humans. One of the treatment modalities for atrial fibrillation is an electrical cardioversion. Electrical cardioversion can result in one of three outcomes: an immediate termination of arrhythmic activity, a delayed termination or unsuccessful termination. The mechanism of delayed termination is unknown. Here we present a model of an atrial fibrillation as a coexistence of several spiral waves pinned to the inhomogeneities in active media. We show that in inhomogeneous system delayed termination can be explained as the unpinning of a spiral wave from inhomogeneities and its termination after collision with the edge of the system. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  5. Dementia and Atrial Fibrillation

    DEFF Research Database (Denmark)

    Pastori, Daniele; Miyazawa, Kazuo; Lip, Gregory Y H

    2018-01-01

    The risk of developing dementia is increased in patients with atrial fibrillation (AF), with the incidence of both conditions increasing with aging. Patients with dementia frequently do not receiving adequate thrombo-prophylaxis, because of the inability to monitor INR and/or to achieve...... in therapeutic range during VKAs therapy, the assessment of cognitive impairment may help identify those patients who may benefit from switching to NOACs. In conclusion, patients with AF and dementia benefit from anticoagulation and should not be denied receiving adequate stroke prevention. Cognitive function...

  6. [Recurrent left atrial myxoma].

    Science.gov (United States)

    Moreno Martínez, Francisco L; Lagomasino Hidalgo, Alvaro; Mirabal Rodríguez, Roger; López Bermúdez, Félix H; López Bernal, Omaida J

    2003-01-01

    Primary cardiac tumors are rare. Mixomas are the most common among them; 75% are located in the left atrium, 20% in the right atrium, and the rest in the ventricles. The seldom appear in atrio-ventricular valves. Recidivant mixoma are also rare, appearing in 1-5% of all patients that have undergone surgical treatment of a mixoma. In this paper we present our experience with a female patient, who 8 years after having been operated of a left atrial mixoma, began with symptoms of mild heart failure. Transthoracic echocardiography revealed recurrence of the tumor, and was therefore subjected to a second open-heart surgery from which she recovered without complications.

  7. Norepinephrine-Induced Adrenergic Activation Strikingly Increased the Atrial Fibrillation Duration through β1- and α1-Adrenergic Receptor-Mediated Signaling in Mice.

    Directory of Open Access Journals (Sweden)

    Kenji Suita

    Full Text Available Atrial fibrillation (AF is the most common arrhythmias among old people. It causes serious long-term health problems affecting the quality of life. It has been suggested that the autonomic nervous system is involved in the onset and maintenance of AF in human. However, investigation of its pathogenesis and potential treatment has been hampered by the lack of suitable AF models in experimental animals.Our aim was to establish a long-lasting AF model in mice. We also investigated the role of adrenergic receptor (AR subtypes, which may be involved in the onset and duration of AF.Trans-esophageal atrial burst pacing in mice could induce AF, as previously shown, but with only a short duration (29.0 ± 8.1 sec. We found that adrenergic activation by intraperitoneal norepinephrine (NE injection strikingly increased the AF duration. It increased the duration to more than 10 minutes, i.e., by more than 20-fold (656.2 ± 104.8 sec; P<0.001. In this model, a prior injection of a specific β1-AR blocker metoprolol and an α1-AR blocker prazosin both significantly attenuated NE-induced elongation of AF. To further explore the mechanisms underlying these receptors' effects on AF, we assessed the SR Ca(2+ leak, a major trigger of AF, and consequent spontaneous SR Ca(2+ release (SCR in atrial myocytes. Consistent with the results of our in-vivo experiments, both metoprolol and prazosin significantly inhibited the NE-induced SR Ca(2+ leak and SCR. These findings suggest that both β1-AR and α1-AR may play important roles in the development of AF.We have established a long-lasting AF model in mice induced by adrenergic activation, which will be valuable in future AF study using experimental animals, such as transgenic mice. We also revealed the important role of β1- and α1-AR-mediated signaling in the development of AF through in-vivo and in-vitro experiments.

  8. Current overview of the genetic background of atrial fibrillation: Possible therapeutic gene targets for the treatment of atrial fibrillation

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    Tetsushi Furukawa, MD, PhD

    2012-06-01

    Full Text Available Atrial fibrillation (AF is the most common arrhythmia. Although AF is known to develop during the course of various cardiac pathological conditions, including valvular heart diseases, congestive heart failure, and hypertension, recent clinical data implicate the additional contribution of genetic factors in the pathogenesis of AF. A familial form of AF has been noted, and 8 loci and 6 responsible genes have been identified. In non-familial AF, genetic risks were originally investigated by the candidate gene approach, and recently by genome-wide association studies (GWASs. GWASs executed in other countries have identified 3 loci: 4q25 near Pitx2, 1q21 in KCNN3, and 16q22 in ZFHX3. Several AF-associated SNPs in 4q25 are also associated with the recurrence rate of AF after catheter pulmonary vein isolation. This review will discuss the genetic underpinnings of AF, in both familial AF and non-familial AF.

  9. CORRELATION BETWEEN CONCENTRATION OF AIR POLLUTANTS AND OCCURRENCE OF CARDIAC ARRHYTHMIAS IN A REGION WITH HUMID CONTINENTAL CLIMATE.

    Science.gov (United States)

    Knezović, Marijana; Pintarić, Sanja; Jelavić, Marko Mornar; Nesek, Višnja; Krstačić, Goran; Vrsalović, Mislav; Šikić, Aljoša; Zeljković, Ivan; Pintarić, Hrvoje

    2017-03-01

    In this study, we investigated the correlation of air temperature, pressure and concentration of air pollutants with the rate of admissions for cardiac arrhythmias at two clinical centers in the area with a humid continental climate. This retrospective study included 3749 patients with arrhythmias admitted to emergency department (ED). They were classified into four groups: supraventricular tachycardia (SVT), ventricular tachycardia (VT), atrial fibrillation/undulation (Afib/Aund), and palpitations (with no ECG changes, or with sinus tachycardia and extrasystoles). The number of patients, values of meteorological parameters (average daily values of air temperature, pressure and relative humidity) and concentrations of air pollutants (particles of dimensions ~10 micrometers or less (PM(10)), ozone (O(3)) and nitrogen dioxide (NO(2))) were collected during a two-year period ( July 2008-June 2010). There were 1650 (44.0%), 1525 (40.7%), 451 (12.0%) and 123 (3.3%) patients with palpitations, Afib/Aund, SVT and VT, respectively. Spearman’s correlation yielded positive correlation between the occurrence of arrhythmias and air humidity on the day (r=0.07), and 1 (r=0.08), 2 (r=0.09) and 3 days before (r=0.09), and NO(2) particles on the day (r=0.08) of ED admission; palpitations and air humidity on the day (r=0.11), and 1 (r=0.09), 2 (r=0.07) and 3 days before (r=0.10), and PM(10) (r=0.11) and NO(2) (r=0.08) particles on the day of ED admission; and Afi b/Aund and air humidity 2 days before (r=0.08) ED admission (pcardiac arrhythmias with air humidity and concentration of air pollutants in the region with a humid continental climate.

  10. Prevention of postoperative atrial fibrillation: novel and safe strategy based on the modulation of the antioxidant system

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    Ramón eRodrigo

    2012-04-01

    Full Text Available Postoperative atrial fibrillation (AF is the most common arrhythmia following cardiac surgery with extracorporeal circulation. The pathogenesis of postoperative AF is multifactorial. Oxidative stress, caused by the unavoidable ischemia-reperfusion event occurring in this setting, is a major contributory factor. ROS-derived effects could result in lipid peroxidation, protein carbonylation or DNA oxidation of cardiac tissue, thus leading to functional and structural myocardial remodeling. The vulnerability of myocardial tissue to the oxidative challenge is also dependent on the activity of the antioxidant system. High ROS levels, overwhelming this system, should result in deleterious cellular effects, such as the induction of necrosis, apoptosis or autophagy. Nevertheless, tissue exposure to low to moderate ROS levels could trigger a survival response with a trend to reinforce the antioxidant defense system. Administration of n-3 polyunsaturated fatty acids (PUFA, known to involve a moderate ROS production, is consistent with a diminished vulnerability to the development of postoperative AF. Accordingly, supplementation of n-3 PUFA successfully reduced the incidence of postoperative AF after coronary bypass grafting. This response is due to an up-regulation of antioxidant enzymes, as shown in experimental models. In turn, non-enzymatic antioxidant reinforcement through vitamin C administration prior to cardiac surgery has also reduced the postoperative AF incidence. Therefore, it should be expected that a mixed therapy result in an improvement of the cardioprotective effect by modulating both components of the antioxidant system. We present available evidence supporting the view of an effective prevention of postoperative AF including a 2-step therapeutic strategy: n-3 PUFA followed by vitamin C supplementation to patients scheduled for cardiac surgery with extracorporeal circulation. The present study should encourage the design of clinical

  11. Cardiac arrhythmias and electrolyte disturbances in colic horses.

    Science.gov (United States)

    Hesselkilde, Eva Z; Almind, Mette E; Petersen, Jesper; Flethøj, Mette; Præstegaard, Kirstine F; Buhl, Rikke

    2014-10-02

    Despite increased focus on cardiac arrhythmias in horses, the nature and prevalence is still poorly described. Case reports suggest that arrhythmias occurring secondary to systemic disease are seen more commonly in the clinic than arrhythmias caused by cardiac disease. The aim of this study was to investigate the prevalence of arrhythmias in colic horses referred for hospital treatment. Associations between electrolyte disturbances and arrhythmias were also investigated. Heart rate was 37.4 ± 3.7 bpm in the control group, and 51.6 ± 11.8 bpm, in the colic group, which was significantly different (P cardiac arrhythmias and electrolytes concentrations in colic horses compared to healthy controls. Although we only observed VPCs in the colic horses, no significant differences between colic horses and controls were found. Despite the colic horses having electrolyte changes at admission no correlation was found between the electrolyte disturbances and cardiac arrhythmias. Although no clear conclusions can be drawn from the present study, the results indicate that relatively mild colic per se is not pro-arrhythmogenic, whereas severe colic probably are more likely to result in ventricular arrhythmia.

  12. CARDIAC ARRHYTHMIAS IN HYPOKALEMIC PERIODIC PARALYSIS : HYPOKALEMIA AS ONLY CAUSE?

    NARCIS (Netherlands)

    Stunnenberg, Bas C.; Deinum, Jaap; Links, Thera P.; Wilde, Arthur A.; Franssen, Hessel; Drost, Gea

    It is unknown how often cardiac arrhythmias occur in hypokalemic periodic paralysis (HypoPP) and if they are caused by hypokalemia alone or other factors. This systematic review shows that cardiac arrhythmias were reported in 27 HypoPP patients. Cases were confirmed genetically (13 with an R528H

  13. Neuroanatomical correlates of severe cardiac arrhythmias in acute ischemic stroke.

    Science.gov (United States)

    Seifert, Frank; Kallmünzer, Bernd; Gutjahr, Isabell; Breuer, Lorenz; Winder, Klemens; Kaschka, Iris; Kloska, Stephan; Doerfler, Arnd; Hilz, Max-Josef; Schwab, Stefan; Köhrmann, Martin

    2015-05-01

    Neurocardiological interactions can cause severe cardiac arrhythmias in patients with acute ischemic stroke. The relationship between the lesion location in the brain and the occurrence of cardiac arrhythmias is still discussed controversially. The aim of the present study was to correlate the lesion location with the occurrence of cardiac arrhythmias in patients with acute ischemic stroke. Cardiac arrhythmias were systematically assessed in patients with acute ischemic stroke during the first 72 h after admission to a monitored stroke unit. Voxel-based lesion-symptom mapping (VLSM) was used to correlate the lesion location with the occurrence of clinically relevant severe arrhythmias. Overall 150 patients, 56 with right-hemispheric and 94 patients with a left-hemispheric lesion, were eligible to be included in the VLSM study. Severe cardiac arrhythmias were present in 49 of these 150 patients (32.7%). We found a significant association (FDR correction, q cardiac arrhythmias. Because left- and right-hemispheric lesions were analyzed separately, the significant findings rely on the 56 patients with right-hemispheric lesions. The data indicate that these areas are involved in central autonomic processing and that right-hemispheric lesions located to these areas are associated with an elevated risk for severe cardiac arrhythmias.

  14. Arrhythmias and ischemia-like ECG changes in Reye's syndrome.

    Science.gov (United States)

    Sarti, A; Cecchi, F; Manetti, A; Busoni, P

    1996-01-01

    We report a fatal case of a child presenting Reye's syndrome associated with a variety of arrhythmias and ischemia-like ST-T ECG changes. At autopsy, fatty infiltration and patchy myocytolysis were detected in sections of the heart. This case report emphasizes cardiac involvement in Reye's syndrome and the possible mechanisms of arrhythmias in this disease.

  15. QTc-prolonging drugs and hospitalizations for cardiac arrhythmias

    NARCIS (Netherlands)

    De Bruin, ML; Hoes, AW; Leufkens, HGM

    2003-01-01

    Cardiac arrhythmia as an adverse effect of noncardiac drugs has been an issue of growing importance during the past few years. In this population-based study, we evaluated the risk for serious cardiac arrhythmias during the use of several noncardiac QTc-prolonging drugs in day-to-day practice, and

  16. Arrhythmia in Acute Right Ventricular Infarction

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    Azin Alizadeh Asl

    2007-09-01

    Full Text Available Acute inferior myocardial infarction (MI frequently involves the right ventricle (RV.1-3 We assessed the prognostic impact of RV myocardial involvement in patients with inferior MI. One hundred seventy patients were admitted to the cardiac care unit of Madani Heart Hospital (Tabriz-Iran with the diagnosis of inferior MI with (group1 or without (group2 the simultaneous involvement of RV during the study period (from 2005 to 2006. Patients presenting within 12h of symptom onset were eligible for inclusion. Patients with simultaneous anterior wall MI or renal impairment (creatinine > 2 mg/dl, as well as those undergoing primary percutaneous translational coronary angioplasty, were excluded. Eighty eight percent of the patients with RVMI and 75% of those with isolated inferior MI had some type of arrhythmia. Atrioventricular (AV block occurred in 42% of the infarctions with RV involvement and only in 29% of the control group. Intra-ventricular conduction disturbance (IVCD was also more frequent in RVMI (29.4% vs. 13.1%, p=0.021, especially right bundle branch block (RBBB (20% vs. 7.4%, P=0.003. There was, however, no meaningful difference in the incidence of left bundle branch block (LBBB between the two groups (3.5% vs. 2.35%, P=0.95. Ventricular fibrillation (VF was observed in 5.2% and 1.2% and ventricular tachycardia in 26% and 12.2% of the patients in groups 1 and 2, respectively. In 27% of patients with RVMI, it was necessary to implant a pacemaker as compared to 10% of those in the control group. Mortality was higher in the patients with inferior infarction extended to the RV (15.3% vs. 3.5%, P= 0.0001. Thus, the differences between the findings in the two groups in terms of the occurrence of post-MI arrhythmias and conduction disorders were quite significant, but there was no meaningful difference with respect to the incidence of LBBB between the two groups. Additionally, patients with inferior MI who also had RV myocardial involvement were

  17. Hundred years of atrial fibrillation: Current knowledge and perspectives

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    Potpara Tatjana

    2010-01-01

    Full Text Available Atrial fibrillation (AF is the most common sustained arrhythmia in general population. AF in humans was first described in 1903. Gradually, it has been well appreciated that AF is not just an acceptable alternative for normal rhythm but rather a serious threat, related to increased mortality and cardiovascular morbidity. AF can precipitate or worsen pre-existing heart failure, may cause the development of tachycardiomyopathy and is an independent risk factor for thromboembolic events, most frequently stroke. It has long been believed that rhythm control is the best therapy for AF. Nowadays there is a clear scientific proof that rhythm control offers no benefit over frequency control, at least for older patients, even with advanced left ventricular dysfunction. However, optimal treatment for younger, highly symptomatic, otherwise healthy AF patients has not been designed. Available antiarrhythmics have considerable proarrhythmic potential or organ toxicity, and new safer drugs are under investigation. Nonpharmacological approaches, namely RF-catheter ablation, are rapidly developing. Prevention of thromboembolism is imperative, and new safer oral anticoagulants have been intensively investigated. Recent randomized studies (PIAF, RACE, STAF, AFFIRM, HOT-CAFE did not solve the issue of optimal arrhythmia treatment, but they emphasized the prevention of thromboembolism based on risk factors, and not on AF type, mainly because asymptomatic episodes of AF may not be clinically recognized.

  18. [Hundred years of atrial fibrillation: current knowledge and perspectives].

    Science.gov (United States)

    Potpara, Tatjana; Grujić, Miodrag

    2010-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia in general population. AF in humans was first described in 1903. Gradually, it has been well appreciated that AF is notjust an acceptable alternative for normal rhythm but rather a serious threat, related to increased mortality and cardiovascular morbidity. AF can precipitate or worsen pre-existing heart failure, may cause the development of tachycardiomyopathy and is an independent risk factor for thromboembolic events, most frequently stroke. It has long been believed that rhythm control is the best therapy for AF. Nowadays there is a clear scientific proof that rhythm control offers no benefit over frequency control, at least for older patients, even with advanced left ventricular dysfunction. However, optimal treatment for younger, highly symptomatic, otherwise healthy AF patients has not been designed. Available antiarrhythmics have considerable proarrhythmic potential or organ toxicity, and new safer drugs are under investigation. Nonpharmacological approaches, namely RF-catheter ablation, are rapidly developing. Prevention of thromboembolism is imperative, and new safer oral anticoagulants have been intensively investigated. Recent randomized studies (PIAF, RACE, STAF, AFFIRM, HOT-CAFE) did not solve the issue of optimal arrhythmia treatment, but they emphasized the prevention of thromboembolism based on risk factors, and not on AF type, mainly because asymptomatic episodes of AF may not be clinically recognised.

  19. Novel biomarkers in cardiology: MicroRNAs in atrial fibrillation.

    Science.gov (United States)

    Orenes-Piñero, Esteban; Quintana-Giner, Miriam; Romero-Aniorte, Ana I; Valdés, Mariano; Marín, Francisco

    2015-01-01

    Atrial fibrillation (AF) is the most common sustained chronic cardiac arrhythmia in clinical practice, which increases the risk of stroke and thromboembolism and is an independent predictor of mortality. The underlying mechanisms involved in the development of AF have yet to be fully elucidated. However, once initiated, AF tends to self-perpetuate, owing to structural and electrical remodeling in the atria. MicroRNAs (miRNAs) represent a sizable sub-group of small non-coding RNAs, which degrades or inhibits the translation of their target mRNAs, thus regulating gene expression and playing an important role in a wide range of biologic processes. Clinically, there is increasing evidence of the potential diagnostic role of miRNAs as biomarkers, representing a novel therapeutic target in AF. The aim of this review is to provide an exhaustive overview of the role of miRNAs in AF and to discuss the diagnostic and therapeutic potential of miRNAs in this arrhythmia. Copyright © 2014 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

  20. Atrial Fibrillation and Fibrosis: Beyond the Cardiomyocyte Centric View

    Science.gov (United States)

    Miragoli, Michele; Glukhov, Alexey V.

    2015-01-01

    Atrial fibrillation (AF) associated with fibrosis is characterized by the appearance of interstitial myofibroblasts. These cells are responsible for the uncontrolled deposition of the extracellular matrix, which pathologically separate cardiomyocyte bundles. The enhanced fibrosis is thought to contribute to arrhythmias “indirectly” because a collagenous septum is a passive substrate for propagation, resulting in impulse conduction block and/or zigzag conduction. However, the emerging results demonstrate that myofibroblasts in vitro also promote arrhythmogenesis due to direct implications upon cardiomyocyte electrophysiology. This electrical interference may be considered beneficial as it resolves any conduction blocks; however, the passive properties of myofibroblasts might cause a delay in impulse propagation, thus promoting AF due to discontinuous slow conduction. Moreover, low-polarized myofibroblasts reduce, via cell-density dependence, the fast driving inward current for cardiac impulse conduction, therefore resulting in arrhythmogenic uniformly slow propagation. Critically, the subsequent reduction in cardiomyocytes resting membrane potential in vitro significantly increases the likelihood of ectopic activity. Myofibroblast densities and the degree of coupling at cellular border zones also impact upon this likelihood. By considering future in vivo studies, which identify myofibroblasts “per se” as a novel targets for cardiac arrhythmias, this review aims to describe the implications of noncardiomyocyte view in the context of AF. PMID:26229964

  1. [Cardiac arrhythmias caused by electrolyte imbalance].

    Science.gov (United States)

    Nishimura, M; Nakayama, K; Ishikawa, Y

    1996-08-01

    Cardiac arrhythmias are known to be caused by many factors. Among them, electrolyte imbalance is the most important because of electrical activity of the heart is composed of transmembrane fluxes of Na+, Ca2+ and K+. In this review article, we describe the effects of high or low concentrations of these electrolytes on the active and passive electrical properties of the membrane in the cardiac tissues, and the mechanisms by which these electrolytes cause abnormal impulse formation and conduction in the heart. Antagonism and synergism of electrolytes and pathological conditions such as digitalis intoxication and ischemia are discussed with respect to not only cardiac electrophysiology but also cellular metabolism. A pathophysiological role of Mg2+ to maintain normal excitation and conduction of the heart is also pointed out.

  2. Deep sequencing of atrial fibrillation patients with mitral valve regurgitation shows no evidence of mosaicism but reveals novel rare germline variants

    DEFF Research Database (Denmark)

    Gregers, Emilie; Ahlberg, Gustav; Christensen, Thea

    2017-01-01

    BACKGROUND: Atrial fibrillation (AF) is the most common cardiac arrhythmia. Valvular heart disease is a strong predictor, yet the underlying molecular mechanisms are unknown. OBJECTIVE: The purpose of this study was to investigate the prevalence of somatic variants in AF candidate genes in an AF...... patient population undergoing surgery for mitral valve regurgitation (MVR) to determine whether these patients are genetically predisposed to AF. METHODS: DNA was extracted from blood and left atrial tissue from 44 AF patients with MVR. Using next-generation sequencing, we investigated 110 genes using...

  3. Sex-specific increase in the prevalence of atrial fibrillation (The Copenhagen City Heart Study)

    DEFF Research Database (Denmark)

    Friberg, Jens; Scharling, Henrik; Gadsbøll, Niels

    2003-01-01

    electrocardiograms (ECGs), was determined in 8,606 patients examined in 1976 to 1978, in 8,943 patients examined in 1981 to 1983, and in 6,733 subjects examined in 1991 to 1994. Changes in prevalence of AF were estimated by logistic regression analysis. In men, the age-standardized prevalence of AF increased from 1......Atrial fibrillation (AF) is the most frequently encountered cardiac arrhythmia. It is a risk factor for stroke and premature death. We studied the temporal changes in the prevalence of AF from 1976 to 1994 in a random population aged 50 to 89 years. The prevalence of AF, diagnosed from...

  4. KCNQ1 mutation Q147R is associated with atrial fibrillation and prolonged QT interval

    DEFF Research Database (Denmark)

    Lundby, Alicia; Ravn, Lasse Steen; Svendsen, Jesper Hastrup

    2007-01-01

    BACKGROUND: Atrial fibrillation (AF) and long QT syndrome (LQTS) are cardiac arrhythmia disorders that have been related to dysfunction of the voltage-gated potassium channel subunit Kv7.1 encoded by the KCNQ1 gene. OBJECTIVE: The purpose of this study was functional assessment of a mutation in Kv7.......1 identified in a proband with permanent AF and prolonged QT interval. We investigated whether this KCNQ1 missense mutation could form the genetic basis for AF and LQTS simultaneously in this patient. METHODS: We investigated the functional consequences of the novel mutation KCNQ1 Q147R by heterologous...

  5. Anaesthetic Management of Parturient with Acute Atrial Fibrillation for Emergency Caesarean Section

    Directory of Open Access Journals (Sweden)

    Madhu Gupta

    2013-01-01

    Full Text Available A 31-year-antenatal lady with critical mitral stenosis presented for emergency caesarean section with fetal distress. She had acute onset atrial fibrillation. She was given a combined spinal epidural (CSE anaesthesia and her arrhythmia was successfully managed after delivery of the baby with intravenous calcium channel blocker. Mitral stenosis is the most common valvular heart disease complicating pregnancy in developing countries. The physiological changes during pregnancy may exacerbate their cardiac symptoms. They may present with complications like congestive cardiac failure, atrial fibrillation, or pulmonary thromboembolism during the antenatal, intrapartum, or postpartum period. Here we discuss the management of parturient woman with high maternal and fetal risk presenting for emergency caesarean. The merits of regional anaesthesia and the importance of invasive monitoring are also discussed.

  6. Screening of KCNN3 in patients with early-onset lone atrial fibrillation

    DEFF Research Database (Denmark)

    Olesen, Morten Sig; Jabbari, Javad; Holst, Anders G

    2011-01-01

    Aims The aim of this study was to screen KCNN3 encoding the small-conductance calcium-activated K(+) channel (SK3) in lone atrial fibrillation patients. Atrial fibrillation (AF) is the most common cardiac arrhythmia. A genome-wide association study has recently associated an intronic single......-nucleotide polymorphism (SNP) in KCNN3 with lone AF. Methods and results We sequenced the coding region and splice junctions of KCNN3 in 209 early-onset lone AF patients, screening for variations. A group of 208 healthy blood donors with normal ECGs and without cardiac symptoms were used as controls. All patients...... and controls were of Danish ethnicity. No mutations were found in the coding regions or splice sites of KCNN3. We found one known exonic synonymous SNP (rs1131820) in KCNN3 that was associated with AF. Both the genotype distribution and allele frequencies of SNP rs1131820 were significantly different between...

  7. NEW ANTIARRHYTHMIC DRUG FOR THE TREATMENT OF ATRIAL FIBRILLATION. STUDY DATA, CLINICAL GUIDELINES, REGULATORY AGENCY RECOMMENDATIONS

    Directory of Open Access Journals (Sweden)

    S. Yu. Martsevich

    2011-01-01

    Full Text Available The main objectives and strategies for treatment of atrial fibrillation (AF, one of the most common cardiac arrhythmia, are seen. A combination of strategies for heart rate control in patients with atrial fibrillation receiving rhythm-controling therapy is preferred at present, according to current guidelines. Amiodarone, one of the most effective anti-arrhythmic drugs with an extensive evidence base, remains the drug of reserve because of serious side effects. A new drug, dronedarone, has electrophysiological properties attributable to all four classes of antiarrhythmic drugs. According to meta-analysis of randomized clinical trials dronedarone is inferior to amiodarone in prevention of AF recurrences, but it is superior to amiodaron in safety. However , in 2011 dronedarone was included in the Food and Drug Administration (FDA list of drugs that require further analysis in connection with appearance of the new information about its safety.

  8. Dronedarone as a new treatment option for atrial fibrillation patients: pharmacokinetics, pharmacodynamics and clinical practice.

    Science.gov (United States)

    Pamukcu, Burak; Lip, Gregory Y H

    2011-01-01

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting 1 - 2% of the population. Despite several developments in antithrombotic, antiatherosclerotic and device-based cardiac therapies, few noteworthy antiarrhythmic drugs have been developed. Dronedarone, a modified analogue of amiodarone, has the pharmacological ability of blocking multiple ion channels. This overview summarizes the pharmacokinetic and pharmacodynamic properties of dronedarone, evaluates its potential application to daily clinical cardiology practice according to the evidence provided by clinical trials, and provides a future clinical perspective for the use of this drug. The readers will gain an understanding of the findings of recent trials performed with dronedarone, which will provide important information for this relatively new antiarrhythmic drug, used for the treatment of atrial fibrillation. Dronedarone provides a reasonable efficacy and safety profile. Recent clinical trials indicate that dronedarone may support maintenance of sinus rhythm, decrease hospitalizations and reduce healthcare costs even in AF patients with structural heart disease but without severe or unstable cardiac failure.

  9. Deglutition-Induced Atrial Tachycardia Localised with Contact Force-Guided Activation Mapping.

    Science.gov (United States)

    McLellan, Alex J A; Bates, Matthew G D; Young, Shane D F; Sparks, Paul B

    2016-11-01

    Deglutition-induced atrial tachycardia is a rare arrhythmia with a poor response to medical therapy. Electrophysiological study is challenging due to the dependence of induction on swallowing. We present a novel approach to management of deglutition-induced atrial tachycardia arising from right superior pulmonary vein. Use of minimal conscious sedation and repeated swallow challenge inductions, together with contact force-guided mapping were key determinants of success. We review published cases, discussing potential mechanisms including oesophageal distension and neural reflexes. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  10. Impact of atrial fibrillation on the cardiovascular system through a lumped-parameter approach

    CERN Document Server

    Scarsoglio, Stefania; Camporeale, Carlo; Ridolfi, Luca

    2014-01-01

    Atrial fibrillation (AF) is the most common arrhythmia affecting millions of people in the Western countries and, due to the widespread impact on the population and its medical relevance, is largely investigated in both clinical and bioengineering sciences. However, some important feedback mechanisms are still not clearly established. The present study aims at understanding the global response of the cardiovascular system during paroxysmal AF through a lumped-parameter approach, which is here performed paying particular attention to the stochastic modeling of the irregular heartbeats and the reduced contractility of the heart. AF can be here analyzed by means of a wide number of hemodynamic parameters and avoiding the presence of other pathologies, which usually accompany AF. Reduced cardiac output with correlated drop of ejection fraction and decreased amount of energy converted to work by the heart during blood pumping, as well as higher left atrial volumes and pressures are some of the most representative ...

  11. Novel Percutaneous Epicardial Autonomic Modulation in the Canine for Atrial Fibrillation: Results of an Efficacy and Safety Study

    Science.gov (United States)

    Madhavan, Malini; Venkatachalam, K. L.; Swale, Matthew J.; DeSimone, Christopher V.; Gard, Joseph J.; Johnson, Susan B.; Suddendorf, Scott H.; Mikell, Susan B.; Ladewig, Dorothy J.; Nosbush, Toni Grabinger; Danielsen, Andrew J.; Knudson, Mark; Asirvatham, Samuel J.

    2016-01-01

    Background Endocardial ablation of atrial ganglionated plexi (GP) has been described for treatment of atrial fibrillation (AF). Our objective in this study was to develop percutaneous epicardial GP ablation in a canine model using novel energy sources and catheters. Methods Phase 1: The efficacy of several modalities to ablate the GP was tested in an open chest canine model (n=10). Phase 2: Percutaneous epicardial ablation of GP was done in 6 dogs using the most efficacious modality identified in phase 1 using 2 novel catheters. Results Phase 1: DC in varying doses [blocking (7 -12μA), electroporation (300-500μA), ablation (3000- 7500μA)], radiofrequency ablation (25–50 W), ultrasound (1.5MHz), and alcohol (2-5ml) injection were successful at 0/8, 4/12, 5/7, 3/8, 1/5 and 5/7 GP sites. DC (500–5000μA) along with alcohol irrigation was tested in phase 2. Phase 2: Percutaneous epicardial ablation of the right atrium, oblique sinus, vein of Marshall, and transverse sinus GP was successful in 5/6 dogs. One dog died of ventricular fibrillation (VF) during DC ablation at 5000 μA. Programmed stimulation induced AF in 6 dogs pre-ablation and no atrial arrhythmia in 3, flutter in 1 and AF in 1 post-ablation. Heart rate, blood pressure, effective atrial refractory period and local atrial electrogram amplitude did not change significantly post-ablation. Microscopic examination showed elimination of GP, and minimal injury to atrial myocardium. Conclusion Percutaneous epicardial ablation of GP using direct current and novel catheters is safe and feasible and may be used as an adjunct to pulmonary vein isolation in the treatment of atrial fibrillation in order to minimize additional atrial myocardial ablation. PMID:26854009

  12. Chronic obstructive pulmonary disease and atrial fibrillation: An unknown relationship.

    Science.gov (United States)

    Goudis, Christos A

    2017-05-01

    Chronic obstructive pulmonary disease (COPD) is independently associated with atrial fibrillation (AF). Decreased oxygenation, hypercapnia, pulmonary hypertension, diastolic dysfunction, oxidative stress, inflammation, changes in atrial size by altered respiratory physiology, increased arrhythmogenicity from nonpulmonary vein foci commonly located in the right atrium, and respiratory drugs have been implicated in the pathogenesis of AF in COPD. The understanding of the relationship between COPD and AF is of particular importance, as the presence of the arrhythmia has significant impact on mortality, especially in COPD exacerbations. On the other hand, COPD in AF is associated with AF progression, success of cardioversion, recurrence of AF after catheter ablation, and increased cardiovascular and all-cause mortality. Treatment of the underlying pulmonary disease and correction of hypoxia and acid-base imbalance represents first-line therapy for COPD patients who develop AF. Cardioselective β-blockers are safe and can be routinely used in COPD. In addition, AF ablation was proved to be efficient and safe, and improves quality of life in these patients. This review presents the association between COPD and AF, describes the pathophysiological mechanisms implicated in AF development in COPD, underlines the prognostic significance of AF in COPD patients and vice versa, and highlights emerging therapeutic approaches in this setting. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  13. Ablation of Atrial Fibrillation in Patients with Congenital Heart Disease.

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    Refaat, Marwan M; Ballout, Jad; Mansour, Moussa

    2017-12-01

    With improved surgical techniques and medical management for patients with congenital heart diseases, more patients are living longer and well into adulthood. This improved survival comes with a price of increased morbidity, mainly secondary to increased risk of tachyarrhythmias. One of the major arrhythmias commonly encountered in this subset of cardiac patients is AF. Similar to the general population, the risk of AF increases with advancing age, and is mainly secondary to the abnormal anatomy, abnormal pressure and volume parameters in the hearts of these patients and to the increased scarring and inflammation seen in the left atrium following multiple surgical procedures. Catheter ablation for AF has been shown to be a very effective treatment modality in patients with refractory AF. However, data and guidelines regarding catheter ablation in patients with congenital heart disease are not well established. This review will shed light on the procedural techniques, success rates and complications of AF catheter ablation in patients with different types of CHD, including atrial septal defects, tetralogy of Fallot, persistent left superior vena cava, heterotaxy syndrome and atrial isomerism, and Ebstein anomaly.

  14. Application of Traditional Chinese Medicine in Treatment of Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Yan Dong

    2017-01-01

    Full Text Available Atrial fibrillation (AF is the most common cardiac arrhythmia, which is related to many cardiac and cerebral vascular diseases, especially stroke. It can therefore increase cardiovascular mortality and all-cause death. The current treatments of AF remain to be western drugs and radiofrequency ablation which are limited by the tolerance of patients, adverse side effects, and high recurrence rate, especially for the elderly. On the contrary, traditional Chinese medicine (TCM with long history of use involves various treatment methods, including Chinese herbal medicines (CHMs or bioactive ingredients, Chinese patent medicines, acupuncture, Qigong, and Tai Chi Chuan. With more and more researches reported, the active roles of TCM in AF management have been discovered. Then it is likely that TCM would be effective preventive means and valuable additional remedy for AF. The potential mechanisms further found by numerous experimental studies showed the distinct characteristics of TCM. Some CHMs or bioactive ingredients are atrial-selective, while others are multichannel and multifunctional. Therefore, in this review we summarized the treatment strategies reported in TCM, with the purpose of providing novel ideas and directions for AF management.

  15. Both Hypothyroidism and Hyperthyroidism Increase Atrial Fibrillation Inducibility in Rats

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    Zhang, Youhua; Dedkov, Eduard I.; Teplitsky, Diana; Weltman, Nathan Y.; Pol, Christine J.; Rajagopalan, Viswanathan; Lee, Bianca; Gerdes, A. Martin

    2014-01-01

    Background Evidence indicates that cardiac hypothyroidism may contribute to heart failure (HF) progression. It is also known that HF is associated with an increased risk of atrial fibrillation (AF). While it is established that hyperthyroidism increases AF incidence, the effect of hypothyroidism on AF is unclear. This study investigated the effects of different thyroid hormone levels, ranging from hypothyroidism to hyperthyroidism on AF inducibility in thyroidectomized rats. Methods and Results Thyroidectomized rats with serum confirmed hypothyroidism 1 month after surgery were randomized into hypothyroid (n=9), euthyroid (n=9) and hyperthyroid (n=9) groups. Rats received placebo, 3.3mg L-thyroxine (T4), or 20 mg T4 pellets (60 day release form) for 2 months, respectively. At the end of treatment, hypothyroid, euthyroid and hyperthyroid status was confirmed. Hypothyroid animals showed cardiac atrophy and reduced cardiac systolic and diastolic function, while hyperthyroid rats exhibited cardiac hypertrophy and increased cardiac function. Hypothyroidism and hyperthyroidism produced opposite electrophysiological changes in heart rates and atrial effective refractory period, but both significantly increased AF susceptibility. AF incidence was 78% in hypothyroid, 67% in hyperthyroid, and the duration of induced AF was also longer, compared with 11% in the euthyroid group (all phyperthyroidism lead to increased AF vulnerability in a rat thyroidectomy model. Our results stress that normal thyroid hormone levels are required to maintain normal cardiac electrophysiology and prevent cardiac arrhythmias and AF. PMID:24036190

  16. Aberrant sodium influx causes cardiomyopathy and atrial fibrillation in mice.

    Science.gov (United States)

    Wan, Elaine; Abrams, Jeffrey; Weinberg, Richard L; Katchman, Alexander N; Bayne, Joseph; Zakharov, Sergey I; Yang, Lin; Morrow, John P; Garan, Hasan; Marx, Steven O

    2016-01-01

    Increased sodium influx via incomplete inactivation of the major cardiac sodium channel Na(V)1.5 is correlated with an increased incidence of atrial fibrillation (AF) in humans. Here, we sought to determine whether increased sodium entry is sufficient to cause the structural and electrophysiological perturbations that are required to initiate and sustain AF. We used mice expressing a human Na(V)1.5 variant with a mutation in the anesthetic-binding site (F1759A-Na(V)1.5) and demonstrated that incomplete Na+ channel inactivation is sufficient to drive structural alterations, including atrial and ventricular enlargement, myofibril disarray, fibrosis and mitochondrial injury, and electrophysiological dysfunctions that together lead to spontaneous and prolonged episodes of AF in these mice. Using this model, we determined that the increase in a persistent sodium current causes heterogeneously prolonged action potential duration and rotors, as well as wave and wavelets in the atria, and thereby mimics mechanistic theories that have been proposed for AF in humans. Acute inhibition of the sodium-calcium exchanger, which targets the downstream effects of enhanced sodium entry, markedly reduced the burden of AF and ventricular arrhythmias in this model, suggesting a potential therapeutic approach for AF. Together, our results indicate that these mice will be important for assessing the cellular mechanisms and potential effectiveness of antiarrhythmic therapies.

  17. TREK-1 (K2P2.1) K+ channels are suppressed in patients with atrial fibrillation and heart failure and provide therapeutic targets for rhythm control.

    Science.gov (United States)

    Lugenbiel, Patrick; Wenz, Fabian; Syren, Pascal; Geschwill, Pascal; Govorov, Katharina; Seyler, Claudia; Frank, Derk; Schweizer, Patrick A; Franke, Jennifer; Weis, Tanja; Bruehl, Claus; Schmack, Bastian; Ruhparwar, Arjang; Karck, Matthias; Frey, Norbert; Katus, Hugo A; Thomas, Dierk

    2017-01-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia. Concomitant heart failure (HF) poses a particular therapeutic challenge and is associated with prolonged atrial electrical refractoriness compared with non-failing hearts. We hypothesized that downregulation of atrial repolarizing TREK-1 (K2P2.1) K+ channels contributes to electrical remodeling during AF with HF, and that TREK-1 gene transfer would provide rhythm control via normalization of atrial effective refractory periods in this AF subset. In patients with chronic AF and HF, atrial TREK-1 mRNA levels were reduced by 82% (left atrium) and 81% (right atrium) compared with sinus rhythm (SR) subjects. Human findings were recapitulated in a porcine model of atrial tachypacing-induced AF and reduced left ventricular function. TREK-1 mRNA (-66%) and protein (-61%) was suppressed in AF animals at 14-day follow-up compared with SR controls. Downregulation of repolarizing TREK-1 channels was associated with prolongation of atrial effective refractory periods versus baseline conditions, consistent with prior observations in humans with HF. In a preclinical therapeutic approach, pigs were randomized to either atrial Ad-TREK-1 gene therapy or sham treatment. Gene transfer effectively